diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 5c724a46..ba4ca435 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -76,6 +76,7 @@ set(INTERNAL_HEADERS
     ${SOURCES_DIR}/internal/catch_exception_translator_registry.hpp
     ${SOURCES_DIR}/internal/catch_fatal_condition_handler.hpp
     ${SOURCES_DIR}/internal/catch_floating_point_helpers.hpp
+    ${SOURCES_DIR}/internal/catch_istream.hpp
     ${SOURCES_DIR}/internal/catch_unique_name.hpp
     ${SOURCES_DIR}/internal/catch_sharding.hpp
     ${SOURCES_DIR}/generators/catch_generator_exception.hpp
@@ -125,11 +126,12 @@ set(INTERNAL_HEADERS
     ${SOURCES_DIR}/internal/catch_result_type.hpp
     ${SOURCES_DIR}/internal/catch_run_context.hpp
     ${SOURCES_DIR}/internal/catch_section.hpp
+    ${SOURCES_DIR}/internal/catch_stdstreams.hpp
     ${SOURCES_DIR}/catch_section_info.hpp
     ${SOURCES_DIR}/catch_session.hpp
     ${SOURCES_DIR}/internal/catch_singletons.hpp
     ${SOURCES_DIR}/internal/catch_startup_exception_registry.hpp
-    ${SOURCES_DIR}/internal/catch_stream.hpp
+    ${SOURCES_DIR}/internal/catch_reusable_string_stream.hpp
     ${SOURCES_DIR}/internal/catch_stream_end_stop.hpp
     ${SOURCES_DIR}/internal/catch_string_manip.hpp
     ${SOURCES_DIR}/internal/catch_stringref.hpp
@@ -180,6 +182,7 @@ set(IMPL_SOURCES
     ${SOURCES_DIR}/internal/catch_exception_translator_registry.cpp
     ${SOURCES_DIR}/internal/catch_fatal_condition_handler.cpp
     ${SOURCES_DIR}/internal/catch_floating_point_helpers.cpp
+    ${SOURCES_DIR}/internal/catch_istream.cpp
     ${SOURCES_DIR}/generators/internal/catch_generators_combined_tu.cpp
     ${SOURCES_DIR}/interfaces/catch_interfaces_combined_tu.cpp
     ${SOURCES_DIR}/interfaces/catch_interfaces_reporter.cpp
@@ -198,9 +201,10 @@ set(IMPL_SOURCES
     ${SOURCES_DIR}/internal/catch_result_type.cpp
     ${SOURCES_DIR}/internal/catch_run_context.cpp
     ${SOURCES_DIR}/internal/catch_section.cpp
+    ${SOURCES_DIR}/internal/catch_stdstreams.cpp
     ${SOURCES_DIR}/catch_session.cpp
     ${SOURCES_DIR}/internal/catch_singletons.cpp
-    ${SOURCES_DIR}/internal/catch_stream.cpp
+    ${SOURCES_DIR}/internal/catch_reusable_string_stream.cpp
     ${SOURCES_DIR}/internal/catch_stringref.cpp
     ${SOURCES_DIR}/internal/catch_string_manip.cpp
     ${SOURCES_DIR}/internal/catch_tag_alias_registry.cpp
diff --git a/src/catch2/catch_all.hpp b/src/catch2/catch_all.hpp
index 79f38f3b..7ba664db 100644
--- a/src/catch2/catch_all.hpp
+++ b/src/catch2/catch_all.hpp
@@ -68,6 +68,7 @@
 #include <catch2/internal/catch_exception_translator_registry.hpp>
 #include <catch2/internal/catch_fatal_condition_handler.hpp>
 #include <catch2/internal/catch_floating_point_helpers.hpp>
+#include <catch2/internal/catch_istream.hpp>
 #include <catch2/internal/catch_lazy_expr.hpp>
 #include <catch2/internal/catch_leak_detector.hpp>
 #include <catch2/internal/catch_list.hpp>
@@ -86,13 +87,14 @@
 #include <catch2/internal/catch_reporter_registry.hpp>
 #include <catch2/internal/catch_reporter_spec_parser.hpp>
 #include <catch2/internal/catch_result_type.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_run_context.hpp>
 #include <catch2/internal/catch_section.hpp>
 #include <catch2/internal/catch_sharding.hpp>
 #include <catch2/internal/catch_singletons.hpp>
 #include <catch2/internal/catch_source_line_info.hpp>
 #include <catch2/internal/catch_startup_exception_registry.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 #include <catch2/internal/catch_stream_end_stop.hpp>
 #include <catch2/internal/catch_string_manip.hpp>
 #include <catch2/internal/catch_stringref.hpp>
diff --git a/src/catch2/catch_approx.cpp b/src/catch2/catch_approx.cpp
index 21652111..b477d6ed 100644
--- a/src/catch2/catch_approx.cpp
+++ b/src/catch2/catch_approx.cpp
@@ -7,7 +7,7 @@
 // SPDX-License-Identifier: BSL-1.0
 #include <catch2/catch_approx.hpp>
 #include <catch2/internal/catch_enforce.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 
 #include <cmath>
 #include <limits>
diff --git a/src/catch2/catch_assertion_result.cpp b/src/catch2/catch_assertion_result.cpp
index 04e00d26..2912c8d3 100644
--- a/src/catch2/catch_assertion_result.cpp
+++ b/src/catch2/catch_assertion_result.cpp
@@ -6,7 +6,7 @@
 
 // SPDX-License-Identifier: BSL-1.0
 #include <catch2/catch_assertion_result.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 
 namespace Catch {
 
diff --git a/src/catch2/catch_config.cpp b/src/catch2/catch_config.cpp
index 1f631f45..d23d66e1 100644
--- a/src/catch2/catch_config.cpp
+++ b/src/catch2/catch_config.cpp
@@ -10,7 +10,6 @@
 #include <catch2/catch_user_config.hpp>
 #include <catch2/internal/catch_compiler_detections.hpp>
 #include <catch2/internal/catch_enforce.hpp>
-#include <catch2/internal/catch_stream.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 #include <catch2/internal/catch_string_manip.hpp>
 #include <catch2/internal/catch_test_spec_parser.hpp>
diff --git a/src/catch2/catch_message.hpp b/src/catch2/catch_message.hpp
index 970ba438..dac7a21d 100644
--- a/src/catch2/catch_message.hpp
+++ b/src/catch2/catch_message.hpp
@@ -9,7 +9,7 @@
 #define CATCH_MESSAGE_HPP_INCLUDED
 
 #include <catch2/internal/catch_result_type.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_stream_end_stop.hpp>
 #include <catch2/internal/catch_message_info.hpp>
 #include <catch2/interfaces/catch_interfaces_capture.hpp>
diff --git a/src/catch2/catch_session.cpp b/src/catch2/catch_session.cpp
index e6ad93a1..df92559b 100644
--- a/src/catch2/catch_session.cpp
+++ b/src/catch2/catch_session.cpp
@@ -11,7 +11,6 @@
 #include <catch2/internal/catch_list.hpp>
 #include <catch2/internal/catch_context.hpp>
 #include <catch2/internal/catch_run_context.hpp>
-#include <catch2/internal/catch_stream.hpp>
 #include <catch2/catch_test_spec.hpp>
 #include <catch2/catch_version.hpp>
 #include <catch2/interfaces/catch_interfaces_reporter.hpp>
@@ -23,6 +22,8 @@
 #include <catch2/interfaces/catch_interfaces_reporter_registry.hpp>
 #include <catch2/interfaces/catch_interfaces_reporter_factory.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
+#include <catch2/internal/catch_istream.hpp>
 
 #include <algorithm>
 #include <cassert>
diff --git a/src/catch2/catch_tostring.hpp b/src/catch2/catch_tostring.hpp
index 92c799f1..08bd935f 100644
--- a/src/catch2/catch_tostring.hpp
+++ b/src/catch2/catch_tostring.hpp
@@ -18,7 +18,7 @@
 #include <catch2/internal/catch_compiler_capabilities.hpp>
 #include <catch2/internal/catch_compiler_detections.hpp>
 #include <catch2/internal/catch_config_wchar.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_void_type.hpp>
 #include <catch2/interfaces/catch_interfaces_enum_values_registry.hpp>
 
diff --git a/src/catch2/interfaces/catch_interfaces_reporter.cpp b/src/catch2/interfaces/catch_interfaces_reporter.cpp
index 9a6cbdc2..b1ad584c 100644
--- a/src/catch2/interfaces/catch_interfaces_reporter.cpp
+++ b/src/catch2/interfaces/catch_interfaces_reporter.cpp
@@ -15,6 +15,7 @@
 #include <catch2/catch_test_case_info.hpp>
 #include <catch2/reporters/catch_reporter_helpers.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
+#include <catch2/internal/catch_istream.hpp>
 
 #include <algorithm>
 #include <cassert>
@@ -44,6 +45,8 @@ namespace Catch {
         return m_customOptions;
     }
 
+    ReporterConfig::~ReporterConfig() = default;
+
     AssertionStats::AssertionStats( AssertionResult const& _assertionResult,
                                     std::vector<MessageInfo> const& _infoMessages,
                                     Totals const& _totals )
diff --git a/src/catch2/interfaces/catch_interfaces_reporter.hpp b/src/catch2/interfaces/catch_interfaces_reporter.hpp
index 1e6c2590..1a2736f7 100644
--- a/src/catch2/interfaces/catch_interfaces_reporter.hpp
+++ b/src/catch2/interfaces/catch_interfaces_reporter.hpp
@@ -40,6 +40,10 @@ namespace Catch {
                         ColourMode colourMode,
                         std::map<std::string, std::string> customOptions );
 
+        ReporterConfig( ReporterConfig&& ) = default;
+        ReporterConfig& operator=( ReporterConfig&& ) = default;
+        ~ReporterConfig(); // = default
+
         Detail::unique_ptr<IStream> takeStream() &&;
         IConfig const* fullConfig() const;
         ColourMode colourMode() const;
diff --git a/src/catch2/internal/catch_console_colour.cpp b/src/catch2/internal/catch_console_colour.cpp
index 25af9585..262d1b6a 100644
--- a/src/catch2/internal/catch_console_colour.cpp
+++ b/src/catch2/internal/catch_console_colour.cpp
@@ -17,7 +17,7 @@
 #include <catch2/internal/catch_enforce.hpp>
 #include <catch2/internal/catch_errno_guard.hpp>
 #include <catch2/interfaces/catch_interfaces_config.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_istream.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
 #include <catch2/internal/catch_context.hpp>
 #include <catch2/internal/catch_platform.hpp>
diff --git a/src/catch2/internal/catch_debug_console.cpp b/src/catch2/internal/catch_debug_console.cpp
index d13cc0bb..5564c6a8 100644
--- a/src/catch2/internal/catch_debug_console.cpp
+++ b/src/catch2/internal/catch_debug_console.cpp
@@ -5,13 +5,16 @@
 //        https://www.boost.org/LICENSE_1_0.txt)
 
 // SPDX-License-Identifier: BSL-1.0
+
 #include <catch2/internal/catch_debug_console.hpp>
+
 #include <catch2/internal/catch_config_android_logwrite.hpp>
-#include <catch2/internal/catch_stream.hpp>
 #include <catch2/internal/catch_platform.hpp>
 #include <catch2/internal/catch_windows_h_proxy.hpp>
+#include <catch2/catch_user_config.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
-#include <iosfwd>
+#include <ostream>
 
 #if defined(CATCH_CONFIG_ANDROID_LOGWRITE)
 #include <android/log.h>
diff --git a/src/catch2/internal/catch_debugger.cpp b/src/catch2/internal/catch_debugger.cpp
index 9b51b1f3..f55adbce 100644
--- a/src/catch2/internal/catch_debugger.cpp
+++ b/src/catch2/internal/catch_debugger.cpp
@@ -9,8 +9,8 @@
 
 #include <catch2/internal/catch_compiler_detections.hpp>
 #include <catch2/internal/catch_errno_guard.hpp>
-#include <catch2/internal/catch_stream.hpp>
 #include <catch2/internal/catch_platform.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
 #if defined(CATCH_PLATFORM_MAC) || defined(CATCH_PLATFORM_IPHONE)
 
diff --git a/src/catch2/internal/catch_enforce.cpp b/src/catch2/internal/catch_enforce.cpp
index 3f4962cb..4bc47ce3 100644
--- a/src/catch2/internal/catch_enforce.cpp
+++ b/src/catch2/internal/catch_enforce.cpp
@@ -6,6 +6,7 @@
 
 // SPDX-License-Identifier: BSL-1.0
 #include <catch2/internal/catch_enforce.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
 #include <stdexcept>
 
diff --git a/src/catch2/internal/catch_enforce.hpp b/src/catch2/internal/catch_enforce.hpp
index 3f81ef1a..db52a0e2 100644
--- a/src/catch2/internal/catch_enforce.hpp
+++ b/src/catch2/internal/catch_enforce.hpp
@@ -10,7 +10,7 @@
 
 #include <catch2/internal/catch_source_line_info.hpp>
 #include <catch2/internal/catch_compiler_capabilities.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 
 #include <exception>
 
diff --git a/src/catch2/internal/catch_enum_values_registry.cpp b/src/catch2/internal/catch_enum_values_registry.cpp
index ef4baf9a..32d0a16d 100644
--- a/src/catch2/internal/catch_enum_values_registry.cpp
+++ b/src/catch2/internal/catch_enum_values_registry.cpp
@@ -7,7 +7,6 @@
 // SPDX-License-Identifier: BSL-1.0
 #include <catch2/internal/catch_enum_values_registry.hpp>
 #include <catch2/internal/catch_string_manip.hpp>
-#include <catch2/internal/catch_stream.hpp>
 
 #include <cassert>
 
diff --git a/src/catch2/internal/catch_fatal_condition_handler.cpp b/src/catch2/internal/catch_fatal_condition_handler.cpp
index 05d4165c..30291d3f 100644
--- a/src/catch2/internal/catch_fatal_condition_handler.cpp
+++ b/src/catch2/internal/catch_fatal_condition_handler.cpp
@@ -31,6 +31,7 @@
 #include <catch2/internal/catch_enforce.hpp>
 #include <catch2/interfaces/catch_interfaces_capture.hpp>
 #include <catch2/internal/catch_windows_h_proxy.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
 #include <algorithm>
 
diff --git a/src/catch2/internal/catch_stream.cpp b/src/catch2/internal/catch_istream.cpp
similarity index 71%
rename from src/catch2/internal/catch_stream.cpp
rename to src/catch2/internal/catch_istream.cpp
index 089a7583..656813b3 100644
--- a/src/catch2/internal/catch_stream.cpp
+++ b/src/catch2/internal/catch_istream.cpp
@@ -5,15 +5,14 @@
 //        https://www.boost.org/LICENSE_1_0.txt)
 
 // SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_istream.hpp>
 #include <catch2/internal/catch_enforce.hpp>
-#include <catch2/internal/catch_stream.hpp>
 #include <catch2/internal/catch_debug_console.hpp>
-#include <catch2/internal/catch_stringref.hpp>
-#include <catch2/internal/catch_singletons.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
 #include <cstdio>
-#include <iostream>
 #include <fstream>
 #include <sstream>
 #include <vector>
@@ -156,57 +155,4 @@ namespace Detail {
         return Detail::make_unique<Detail::FileStream>( filename );
     }
 
-
-    // This class encapsulates the idea of a pool of ostringstreams that can be reused.
-    struct StringStreams {
-        std::vector<Detail::unique_ptr<std::ostringstream>> m_streams;
-        std::vector<std::size_t> m_unused;
-        std::ostringstream m_referenceStream; // Used for copy state/ flags from
-
-        auto add() -> std::size_t {
-            if( m_unused.empty() ) {
-                m_streams.push_back( Detail::make_unique<std::ostringstream>() );
-                return m_streams.size()-1;
-            }
-            else {
-                auto index = m_unused.back();
-                m_unused.pop_back();
-                return index;
-            }
-        }
-
-        void release( std::size_t index ) {
-            m_streams[index]->copyfmt( m_referenceStream ); // Restore initial flags and other state
-            m_unused.push_back(index);
-        }
-    };
-
-    ReusableStringStream::ReusableStringStream()
-    :   m_index( Singleton<StringStreams>::getMutable().add() ),
-        m_oss( Singleton<StringStreams>::getMutable().m_streams[m_index].get() )
-    {}
-
-    ReusableStringStream::~ReusableStringStream() {
-        static_cast<std::ostringstream*>( m_oss )->str("");
-        m_oss->clear();
-        Singleton<StringStreams>::getMutable().release( m_index );
-    }
-
-    std::string ReusableStringStream::str() const {
-        return static_cast<std::ostringstream*>( m_oss )->str();
-    }
-
-    void ReusableStringStream::str( std::string const& str ) {
-        static_cast<std::ostringstream*>( m_oss )->str( str );
-    }
-
-
-    ///////////////////////////////////////////////////////////////////////////
-
-
-#ifndef CATCH_CONFIG_NOSTDOUT // If you #define this you must implement these functions
-    std::ostream& cout() { return std::cout; }
-    std::ostream& cerr() { return std::cerr; }
-    std::ostream& clog() { return std::clog; }
-#endif
 }
diff --git a/src/catch2/internal/catch_stream.hpp b/src/catch2/internal/catch_istream.hpp
similarity index 54%
rename from src/catch2/internal/catch_stream.hpp
rename to src/catch2/internal/catch_istream.hpp
index cdc50996..629816c8 100644
--- a/src/catch2/internal/catch_stream.hpp
+++ b/src/catch2/internal/catch_istream.hpp
@@ -5,10 +5,9 @@
 //        https://www.boost.org/LICENSE_1_0.txt)
 
 // SPDX-License-Identifier: BSL-1.0
-#ifndef CATCH_STREAM_HPP_INCLUDED
-#define CATCH_STREAM_HPP_INCLUDED
+#ifndef CATCH_ISTREAM_HPP_INCLUDED
+#define CATCH_ISTREAM_HPP_INCLUDED
 
-#include <catch2/internal/catch_compiler_detections.hpp>
 #include <catch2/internal/catch_noncopyable.hpp>
 #include <catch2/internal/catch_unique_ptr.hpp>
 
@@ -19,10 +18,6 @@
 
 namespace Catch {
 
-    std::ostream& cout();
-    std::ostream& cerr();
-    std::ostream& clog();
-
     class IStream {
     public:
         virtual ~IStream(); // = default
@@ -54,41 +49,6 @@ namespace Catch {
      */
     auto makeStream( std::string const& filename ) -> Detail::unique_ptr<IStream>;
 
-    class ReusableStringStream : Detail::NonCopyable {
-        std::size_t m_index;
-        std::ostream* m_oss;
-    public:
-        ReusableStringStream();
-        ~ReusableStringStream();
-
-        //! Returns the serialized state
-        std::string str() const;
-        //! Sets internal state to `str`
-        void str(std::string const& str);
-
-#if defined(CATCH_COMPILER_GCC)
-#pragma GCC diagnostic push
-// Old versions of GCC do not understand -Wnonnull-compare
-#pragma GCC diagnostic ignored "-Wpragmas"
-// Streaming a function pointer triggers Waddress and Wnonnull-compare
-// on GCC, because it implicitly converts it to bool and then decides
-// that the check it uses (a? true : false) is tautological and cannot
-// be null...
-#pragma GCC diagnostic ignored "-Waddress"
-#pragma GCC diagnostic ignored "-Wnonnull-compare"
-#endif
-
-        template<typename T>
-        auto operator << ( T const& value ) -> ReusableStringStream& {
-            *m_oss << value;
-            return *this;
-        }
-
-#if defined(CATCH_COMPILER_GCC)
-#pragma GCC diagnostic pop
-#endif
-        auto get() -> std::ostream& { return *m_oss; }
-    };
 }
 
 #endif // CATCH_STREAM_HPP_INCLUDED
diff --git a/src/catch2/internal/catch_output_redirect.cpp b/src/catch2/internal/catch_output_redirect.cpp
index a6bae64f..6d1569a6 100644
--- a/src/catch2/internal/catch_output_redirect.cpp
+++ b/src/catch2/internal/catch_output_redirect.cpp
@@ -9,6 +9,7 @@
 
 #include <catch2/internal/catch_compiler_detections.hpp>
 #include <catch2/internal/catch_enforce.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
 
 #include <cstdio>
 #include <cstring>
diff --git a/src/catch2/internal/catch_output_redirect.hpp b/src/catch2/internal/catch_output_redirect.hpp
index 021b6d5e..2eaa0135 100644
--- a/src/catch2/internal/catch_output_redirect.hpp
+++ b/src/catch2/internal/catch_output_redirect.hpp
@@ -9,7 +9,7 @@
 #define CATCH_OUTPUT_REDIRECT_HPP_INCLUDED
 
 #include <catch2/internal/catch_platform.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_compiler_capabilities.hpp>
 #include <catch2/internal/catch_compiler_detections.hpp>
 
diff --git a/src/catch2/internal/catch_reusable_string_stream.cpp b/src/catch2/internal/catch_reusable_string_stream.cpp
new file mode 100644
index 00000000..9b082423
--- /dev/null
+++ b/src/catch2/internal/catch_reusable_string_stream.cpp
@@ -0,0 +1,62 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#include <catch2/internal/catch_reusable_string_stream.hpp>
+#include <catch2/internal/catch_singletons.hpp>
+#include <catch2/internal/catch_unique_ptr.hpp>
+
+#include <cstdio>
+#include <sstream>
+#include <vector>
+
+namespace Catch {
+
+    // This class encapsulates the idea of a pool of ostringstreams that can be reused.
+    struct StringStreams {
+        std::vector<Detail::unique_ptr<std::ostringstream>> m_streams;
+        std::vector<std::size_t> m_unused;
+        std::ostringstream m_referenceStream; // Used for copy state/ flags from
+
+        auto add() -> std::size_t {
+            if( m_unused.empty() ) {
+                m_streams.push_back( Detail::make_unique<std::ostringstream>() );
+                return m_streams.size()-1;
+            }
+            else {
+                auto index = m_unused.back();
+                m_unused.pop_back();
+                return index;
+            }
+        }
+
+        void release( std::size_t index ) {
+            m_streams[index]->copyfmt( m_referenceStream ); // Restore initial flags and other state
+            m_unused.push_back(index);
+        }
+    };
+
+    ReusableStringStream::ReusableStringStream()
+    :   m_index( Singleton<StringStreams>::getMutable().add() ),
+        m_oss( Singleton<StringStreams>::getMutable().m_streams[m_index].get() )
+    {}
+
+    ReusableStringStream::~ReusableStringStream() {
+        static_cast<std::ostringstream*>( m_oss )->str("");
+        m_oss->clear();
+        Singleton<StringStreams>::getMutable().release( m_index );
+    }
+
+    std::string ReusableStringStream::str() const {
+        return static_cast<std::ostringstream*>( m_oss )->str();
+    }
+
+    void ReusableStringStream::str( std::string const& str ) {
+        static_cast<std::ostringstream*>( m_oss )->str( str );
+    }
+
+
+}
diff --git a/src/catch2/internal/catch_reusable_string_stream.hpp b/src/catch2/internal/catch_reusable_string_stream.hpp
new file mode 100644
index 00000000..21d3162c
--- /dev/null
+++ b/src/catch2/internal/catch_reusable_string_stream.hpp
@@ -0,0 +1,58 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_REUSABLE_STRING_STREAM_HPP_INCLUDED
+#define CATCH_REUSABLE_STRING_STREAM_HPP_INCLUDED
+
+#include <catch2/internal/catch_compiler_detections.hpp>
+#include <catch2/internal/catch_noncopyable.hpp>
+
+#include <iosfwd>
+#include <cstddef>
+#include <ostream>
+#include <string>
+
+namespace Catch {
+
+    class ReusableStringStream : Detail::NonCopyable {
+        std::size_t m_index;
+        std::ostream* m_oss;
+    public:
+        ReusableStringStream();
+        ~ReusableStringStream();
+
+        //! Returns the serialized state
+        std::string str() const;
+        //! Sets internal state to `str`
+        void str(std::string const& str);
+
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+// Old versions of GCC do not understand -Wnonnull-compare
+#pragma GCC diagnostic ignored "-Wpragmas"
+// Streaming a function pointer triggers Waddress and Wnonnull-compare
+// on GCC, because it implicitly converts it to bool and then decides
+// that the check it uses (a? true : false) is tautological and cannot
+// be null...
+#pragma GCC diagnostic ignored "-Waddress"
+#pragma GCC diagnostic ignored "-Wnonnull-compare"
+#endif
+
+        template<typename T>
+        auto operator << ( T const& value ) -> ReusableStringStream& {
+            *m_oss << value;
+            return *this;
+        }
+
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+        auto get() -> std::ostream& { return *m_oss; }
+    };
+}
+
+#endif // CATCH_REUSABLE_STRING_STREAM_HPP_INCLUDED
diff --git a/src/catch2/internal/catch_stdstreams.cpp b/src/catch2/internal/catch_stdstreams.cpp
new file mode 100644
index 00000000..21a0e4e6
--- /dev/null
+++ b/src/catch2/internal/catch_stdstreams.cpp
@@ -0,0 +1,24 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_stdstreams.hpp>
+
+#include <catch2/catch_user_config.hpp>
+
+#include <iostream>
+
+namespace Catch {
+
+// If you #define this you must implement these functions
+#if !defined( CATCH_CONFIG_NOSTDOUT )
+    std::ostream& cout() { return std::cout; }
+    std::ostream& cerr() { return std::cerr; }
+    std::ostream& clog() { return std::clog; }
+#endif
+
+} // namespace Catch
diff --git a/src/catch2/internal/catch_stdstreams.hpp b/src/catch2/internal/catch_stdstreams.hpp
new file mode 100644
index 00000000..39d8bd75
--- /dev/null
+++ b/src/catch2/internal/catch_stdstreams.hpp
@@ -0,0 +1,22 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#ifndef CATCH_STDSTREAMS_HPP_INCLUDED
+#define CATCH_STDSTREAMS_HPP_INCLUDED
+
+#include <iosfwd>
+
+namespace Catch {
+
+    std::ostream& cout();
+    std::ostream& cerr();
+    std::ostream& clog();
+
+} // namespace Catch
+
+#endif
diff --git a/src/catch2/internal/catch_to_string.hpp b/src/catch2/internal/catch_to_string.hpp
index d8ff35cf..15b24e19 100644
--- a/src/catch2/internal/catch_to_string.hpp
+++ b/src/catch2/internal/catch_to_string.hpp
@@ -11,7 +11,7 @@
 #include <string>
 
 #include <catch2/internal/catch_compiler_capabilities.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 
 namespace Catch {
     template <typename T>
diff --git a/src/catch2/internal/catch_xmlwriter.hpp b/src/catch2/internal/catch_xmlwriter.hpp
index edeb64a2..55633937 100644
--- a/src/catch2/internal/catch_xmlwriter.hpp
+++ b/src/catch2/internal/catch_xmlwriter.hpp
@@ -8,7 +8,7 @@
 #ifndef CATCH_XMLWRITER_HPP_INCLUDED
 #define CATCH_XMLWRITER_HPP_INCLUDED
 
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 
 #include <iosfwd>
diff --git a/src/catch2/matchers/internal/catch_matchers_combined_tu.cpp b/src/catch2/matchers/internal/catch_matchers_combined_tu.cpp
index de713b3b..6ec878b0 100644
--- a/src/catch2/matchers/internal/catch_matchers_combined_tu.cpp
+++ b/src/catch2/matchers/internal/catch_matchers_combined_tu.cpp
@@ -43,7 +43,7 @@ namespace Catch {
 // vvv formerly catch_matchers_container_properties.cpp vvv //
 //////////////////////////////////////////////////////////////
 #include <catch2/matchers/catch_matchers_container_properties.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 
 namespace Catch {
 namespace Matchers {
diff --git a/src/catch2/reporters/catch_reporter_combined_tu.cpp b/src/catch2/reporters/catch_reporter_combined_tu.cpp
index 6cfe78ba..cbbb03b0 100644
--- a/src/catch2/reporters/catch_reporter_combined_tu.cpp
+++ b/src/catch2/reporters/catch_reporter_combined_tu.cpp
@@ -24,7 +24,7 @@
 #include <catch2/internal/catch_console_width.hpp>
 #include <catch2/internal/catch_errno_guard.hpp>
 #include <catch2/internal/catch_textflow.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_string_manip.hpp>
 #include <catch2/internal/catch_console_colour.hpp>
 #include <catch2/catch_tostring.hpp>
diff --git a/src/catch2/reporters/catch_reporter_common_base.cpp b/src/catch2/reporters/catch_reporter_common_base.cpp
index 68a24eef..f4736ab2 100644
--- a/src/catch2/reporters/catch_reporter_common_base.cpp
+++ b/src/catch2/reporters/catch_reporter_common_base.cpp
@@ -10,7 +10,7 @@
 
 #include <catch2/reporters/catch_reporter_helpers.hpp>
 #include <catch2/internal/catch_console_colour.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_istream.hpp>
 
 
 namespace Catch {
diff --git a/src/catch2/reporters/catch_reporter_console.cpp b/src/catch2/reporters/catch_reporter_console.cpp
index 19a48a78..2d7f22b9 100644
--- a/src/catch2/reporters/catch_reporter_console.cpp
+++ b/src/catch2/reporters/catch_reporter_console.cpp
@@ -14,7 +14,7 @@
 #include <catch2/internal/catch_string_manip.hpp>
 #include <catch2/catch_version.hpp>
 #include <catch2/internal/catch_textflow.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/internal/catch_stringref.hpp>
 #include <catch2/catch_test_case_info.hpp>
 #include <catch2/internal/catch_console_width.hpp>
diff --git a/src/catch2/reporters/catch_reporter_multi.cpp b/src/catch2/reporters/catch_reporter_multi.cpp
index e8cf7bdf..e7ba7e5d 100644
--- a/src/catch2/reporters/catch_reporter_multi.cpp
+++ b/src/catch2/reporters/catch_reporter_multi.cpp
@@ -9,7 +9,9 @@
 
 #include <catch2/catch_config.hpp>
 #include <catch2/internal/catch_move_and_forward.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_stdstreams.hpp>
+
+#include <ostream>
 
 namespace Catch {
     void MultiReporter::updatePreferences(IEventListener const& reporterish) {
diff --git a/tests/ExtraTests/X04-DisabledExceptions-CustomHandler.cpp b/tests/ExtraTests/X04-DisabledExceptions-CustomHandler.cpp
index b506d8b8..725440ec 100644
--- a/tests/ExtraTests/X04-DisabledExceptions-CustomHandler.cpp
+++ b/tests/ExtraTests/X04-DisabledExceptions-CustomHandler.cpp
@@ -8,11 +8,13 @@
 
 #include <catch2/catch_test_macros.hpp>
 
+#include <iostream>
+
 namespace Catch {
     [[noreturn]]
     void throw_exception(std::exception const& e) {
-        Catch::cerr() << "====== CUSTOM HANDLER ====== run terminates because an exception was thrown.\n"
-                      << "The message was: " << e.what() << '\n';
+        std::cerr << "====== CUSTOM HANDLER ====== run terminates because an exception was thrown.\n"
+                  << "The message was: " << e.what() << '\n';
         // Avoid abort and other exceptional exits -- there is no way
         // to tell CMake that abort is the desired outcome of a test.
         exit(1);
diff --git a/tests/SelfTest/IntrospectiveTests/ColourImpl.tests.cpp b/tests/SelfTest/IntrospectiveTests/ColourImpl.tests.cpp
index 716d6033..83501cae 100644
--- a/tests/SelfTest/IntrospectiveTests/ColourImpl.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/ColourImpl.tests.cpp
@@ -8,6 +8,7 @@
 
 #include <catch2/catch_test_macros.hpp>
 #include <catch2/internal/catch_console_colour.hpp>
+#include <catch2/internal/catch_istream.hpp>
 
 #include <sstream>
 
diff --git a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
index e4554fca..5288709d 100644
--- a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
@@ -17,7 +17,7 @@
 #include <catch2/internal/catch_enforce.hpp>
 #include <catch2/internal/catch_list.hpp>
 #include <catch2/internal/catch_reporter_registry.hpp>
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_istream.hpp>
 #include <catch2/matchers/catch_matchers_string.hpp>
 #include <catch2/reporters/catch_reporter_helpers.hpp>
 #include <catch2/reporters/catch_reporter_event_listener.hpp>
diff --git a/tests/SelfTest/IntrospectiveTests/Stream.tests.cpp b/tests/SelfTest/IntrospectiveTests/Stream.tests.cpp
index 9d647b0d..5ad92e8c 100644
--- a/tests/SelfTest/IntrospectiveTests/Stream.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/Stream.tests.cpp
@@ -8,7 +8,7 @@
 
 #include <catch2/catch_test_macros.hpp>
 
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_istream.hpp>
 
 TEST_CASE( "Cout stream properly declares it writes to stdout", "[streams]" ) {
     REQUIRE( Catch::makeStream( "-" )->isConsole() );
diff --git a/tests/SelfTest/IntrospectiveTests/Xml.tests.cpp b/tests/SelfTest/IntrospectiveTests/Xml.tests.cpp
index 678d8c87..226e737c 100644
--- a/tests/SelfTest/IntrospectiveTests/Xml.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/Xml.tests.cpp
@@ -9,7 +9,7 @@
 #include <catch2/catch_test_macros.hpp>
 #include <catch2/internal/catch_xmlwriter.hpp>
 
-#include <catch2/internal/catch_stream.hpp>
+#include <catch2/internal/catch_reusable_string_stream.hpp>
 #include <catch2/matchers/catch_matchers_string.hpp>
 
 #include <sstream>