diff --git a/src/catch2/catch_config.cpp b/src/catch2/catch_config.cpp
index e6a5b2ed..6d6e0831 100644
--- a/src/catch2/catch_config.cpp
+++ b/src/catch2/catch_config.cpp
@@ -107,8 +107,8 @@ namespace Catch {
         return m_data.reporterSpecifications;
     }
 
-    std::ostream& Config::getReporterOutputStream(std::size_t reporterIdx) const {
-        return m_reporterStreams.at(reporterIdx)->stream();
+    IStream const* Config::getReporterOutputStream(std::size_t reporterIdx) const {
+        return m_reporterStreams.at(reporterIdx).get();
     }
 
     TestSpec const& Config::testSpec() const { return m_testSpec; }
@@ -118,7 +118,7 @@ namespace Catch {
 
     // IConfig interface
     bool Config::allowThrows() const                   { return !m_data.noThrow; }
-    std::ostream& Config::defaultStream() const        { return m_defaultStream->stream(); }
+    IStream const* Config::defaultStream() const       { return m_defaultStream.get(); }
     StringRef Config::name() const { return m_data.name.empty() ? m_data.processName : m_data.name; }
     bool Config::includeSuccessfulResults() const      { return m_data.showSuccessfulTests; }
     bool Config::warnAboutMissingAssertions() const {
diff --git a/src/catch2/catch_config.hpp b/src/catch2/catch_config.hpp
index 2795d42e..7b33fa71 100644
--- a/src/catch2/catch_config.hpp
+++ b/src/catch2/catch_config.hpp
@@ -21,7 +21,7 @@
 
 namespace Catch {
 
-    struct IStream;
+    class IStream;
 
     struct ConfigData {
         struct ReporterAndFile {
@@ -91,7 +91,7 @@ namespace Catch {
         bool listReporters() const;
 
         std::vector<ConfigData::ReporterAndFile> const& getReportersAndOutputFiles() const;
-        std::ostream& getReporterOutputStream(std::size_t reporterIdx) const;
+        IStream const* getReporterOutputStream(std::size_t reporterIdx) const;
 
         std::vector<std::string> const& getTestsOrTags() const override;
         std::vector<std::string> const& getSectionsToRun() const override;
@@ -103,7 +103,7 @@ namespace Catch {
 
         // IConfig interface
         bool allowThrows() const override;
-        std::ostream& defaultStream() const override;
+        IStream const* defaultStream() const override;
         StringRef name() const override;
         bool includeSuccessfulResults() const override;
         bool warnAboutMissingAssertions() const override;
diff --git a/src/catch2/catch_session.cpp b/src/catch2/catch_session.cpp
index a4a78bb6..f20531e3 100644
--- a/src/catch2/catch_session.cpp
+++ b/src/catch2/catch_session.cpp
@@ -44,7 +44,7 @@ namespace Catch {
         IStreamingReporterPtr makeReporter(Config const* config) {
             if (Catch::getRegistryHub().getReporterRegistry().getListeners().empty()
                     && config->getReportersAndOutputFiles().size() == 1) {
-                auto& stream = config->getReporterOutputStream(0);
+                auto stream = config->getReporterOutputStream(0);
                 return createReporter(config->getReportersAndOutputFiles()[0].reporterName, ReporterConfig(config, stream));
             }
 
@@ -57,7 +57,7 @@ namespace Catch {
 
             std::size_t reporterIdx = 0;
             for (auto const& reporterAndFile : config->getReportersAndOutputFiles()) {
-                auto& stream = config->getReporterOutputStream(reporterIdx);
+                auto stream = config->getReporterOutputStream(reporterIdx);
                 multi->addReporter(createReporter(reporterAndFile.reporterName, ReporterConfig(config, stream)));
                 reporterIdx++;
             }
diff --git a/src/catch2/interfaces/catch_interfaces_config.hpp b/src/catch2/interfaces/catch_interfaces_config.hpp
index 4b2bd365..6c17081a 100644
--- a/src/catch2/interfaces/catch_interfaces_config.hpp
+++ b/src/catch2/interfaces/catch_interfaces_config.hpp
@@ -55,13 +55,14 @@ namespace Catch {
     }; };
 
     class TestSpec;
+    class IStream;
 
     struct IConfig : Detail::NonCopyable {
 
         virtual ~IConfig();
 
         virtual bool allowThrows() const = 0;
-        virtual std::ostream& defaultStream() const = 0;
+        virtual IStream const* defaultStream() const = 0;
         virtual StringRef name() const = 0;
         virtual bool includeSuccessfulResults() const = 0;
         virtual bool shouldDebugBreak() const = 0;
diff --git a/src/catch2/interfaces/catch_interfaces_reporter.cpp b/src/catch2/interfaces/catch_interfaces_reporter.cpp
index e5d3921f..5f5d274a 100644
--- a/src/catch2/interfaces/catch_interfaces_reporter.cpp
+++ b/src/catch2/interfaces/catch_interfaces_reporter.cpp
@@ -20,10 +20,10 @@
 
 namespace Catch {
 
-    ReporterConfig::ReporterConfig( IConfig const* _fullConfig, std::ostream& _stream )
-    :   m_stream( &_stream ), m_fullConfig( _fullConfig ) {}
+    ReporterConfig::ReporterConfig( IConfig const* _fullConfig, IStream const* _stream )
+    :   m_stream( _stream ), m_fullConfig( _fullConfig ) {}
 
-    std::ostream& ReporterConfig::stream() const { return *m_stream; }
+    IStream const* ReporterConfig::stream() const { return m_stream; }
     IConfig const * ReporterConfig::fullConfig() const { return m_fullConfig; }
 
     AssertionStats::AssertionStats( AssertionResult const& _assertionResult,
diff --git a/src/catch2/interfaces/catch_interfaces_reporter.hpp b/src/catch2/interfaces/catch_interfaces_reporter.hpp
index c05648b7..41cf426b 100644
--- a/src/catch2/interfaces/catch_interfaces_reporter.hpp
+++ b/src/catch2/interfaces/catch_interfaces_reporter.hpp
@@ -30,15 +30,16 @@ namespace Catch {
     struct TestCaseInfo;
     class TestCaseHandle;
     struct IConfig;
+    class IStream;
 
     struct ReporterConfig {
-        ReporterConfig( IConfig const* _fullConfig, std::ostream& _stream );
+        ReporterConfig( IConfig const* _fullConfig, IStream const* _stream );
 
-        std::ostream& stream() const;
+        IStream const* stream() const;
         IConfig const* fullConfig() const;
 
     private:
-        std::ostream* m_stream;
+        IStream const* m_stream;
         IConfig const* m_fullConfig;
     };
 
diff --git a/src/catch2/internal/catch_console_colour.cpp b/src/catch2/internal/catch_console_colour.cpp
index b3e4934e..b3d583d2 100644
--- a/src/catch2/internal/catch_console_colour.cpp
+++ b/src/catch2/internal/catch_console_colour.cpp
@@ -160,7 +160,7 @@ namespace {
         void setColour( const char* _escapeCode ) {
             // The escape sequence must be flushed to console, otherwise if
             // stdin and stderr are intermixed, we'd get accidentally coloured output.
-            getCurrentContext().getConfig()->defaultStream()
+            getCurrentContext().getConfig()->defaultStream()->stream()
                 << '\033' << _escapeCode << std::flush;
         }
     };
diff --git a/src/catch2/internal/catch_stream.hpp b/src/catch2/internal/catch_stream.hpp
index 77a35760..1b92b4dc 100644
--- a/src/catch2/internal/catch_stream.hpp
+++ b/src/catch2/internal/catch_stream.hpp
@@ -22,7 +22,8 @@ namespace Catch {
     std::ostream& cerr();
     std::ostream& clog();
 
-    struct IStream {
+    class IStream {
+    public:
         virtual ~IStream(); // = default
         virtual std::ostream& stream() const = 0;
         // Win32 colour supports requires us to identify whether a stream
diff --git a/src/catch2/reporters/catch_reporter_common_base.hpp b/src/catch2/reporters/catch_reporter_common_base.hpp
index 235c2606..b7610a93 100644
--- a/src/catch2/reporters/catch_reporter_common_base.hpp
+++ b/src/catch2/reporters/catch_reporter_common_base.hpp
@@ -9,6 +9,7 @@
 #define CATCH_REPORTER_COMMON_BASE_HPP_INCLUDED
 
 #include <catch2/interfaces/catch_interfaces_reporter.hpp>
+#include <catch2/internal/catch_stream.hpp>
 
 namespace Catch {
     /**
@@ -23,13 +24,19 @@ namespace Catch {
      */
     class ReporterBase : public IEventListener {
     protected:
-        //! Stream to write the output to
+        //! The stream wrapper as passed to us by outside code
+        IStream const* m_wrapped_stream;
+        //! Cached output stream from `m_wrapped_stream` to reduce
+        //! number of indirect calls needed to write output.
         std::ostream& m_stream;
 
+
+
     public:
         ReporterBase( ReporterConfig const& config ):
             IEventListener( config.fullConfig() ),
-            m_stream( config.stream() ) {}
+            m_wrapped_stream( config.stream() ),
+            m_stream( m_wrapped_stream->stream() ) {}
 
 
         /**
diff --git a/src/catch2/reporters/catch_reporter_console.cpp b/src/catch2/reporters/catch_reporter_console.cpp
index d5dd89c5..e79d6a63 100644
--- a/src/catch2/reporters/catch_reporter_console.cpp
+++ b/src/catch2/reporters/catch_reporter_console.cpp
@@ -355,7 +355,7 @@ public:
 
 ConsoleReporter::ConsoleReporter(ReporterConfig const& config)
     : StreamingReporterBase(config),
-    m_tablePrinter(Detail::make_unique<TablePrinter>(config.stream(),
+    m_tablePrinter(Detail::make_unique<TablePrinter>(m_stream,
         [&config]() -> std::vector<ColumnInfo> {
         if (config.fullConfig()->benchmarkNoAnalysis())
         {
diff --git a/src/catch2/reporters/catch_reporter_xml.cpp b/src/catch2/reporters/catch_reporter_xml.cpp
index 8c3338cb..78fa8647 100644
--- a/src/catch2/reporters/catch_reporter_xml.cpp
+++ b/src/catch2/reporters/catch_reporter_xml.cpp
@@ -24,7 +24,7 @@
 namespace Catch {
     XmlReporter::XmlReporter( ReporterConfig const& _config )
     :   StreamingReporterBase( _config ),
-        m_xml(_config.stream())
+        m_xml(m_stream)
     {
         m_preferences.shouldRedirectStdOut = true;
         m_preferences.shouldReportAllAssertions = true;
diff --git a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
index 40ae0179..a2416042 100644
--- a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
@@ -16,6 +16,7 @@
 #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/matchers/catch_matchers_string.hpp>
 #include <catch2/reporters/catch_reporter_helpers.hpp>
 #include <catch2/reporters/catch_reporter_event_listener.hpp>
@@ -24,6 +25,16 @@
 
 #include <sstream>
 
+namespace {
+    class StringIStream : public Catch::IStream {
+    public:
+        std::ostream& stream() const override { return sstr; }
+        std::string str() const { return sstr.str(); }
+    private:
+        mutable std::stringstream sstr;
+    };
+}
+
 TEST_CASE( "The default listing implementation write to provided stream",
            "[reporters][reporter-helpers]" ) {
     using Catch::Matchers::ContainsSubstring;
@@ -72,11 +83,11 @@ TEST_CASE( "Reporter's write listings to provided stream", "[reporters]" ) {
 
     for (auto const& factory : factories) {
         INFO("Tested reporter: " << factory.first);
-        std::stringstream sstream;
+        StringIStream sstream;
 
         Catch::ConfigData config_data;
         Catch::Config config( config_data );
-        Catch::ReporterConfig rep_config( &config, sstream );
+        Catch::ReporterConfig rep_config( &config, &sstream );
         auto reporter = factory.second->create( rep_config );
 
         DYNAMIC_SECTION( factory.first << " reporter lists tags" ) {
@@ -162,8 +173,8 @@ TEST_CASE("Multireporter calls reporters and listeners in correct order",
 
     Catch::ConfigData config_data;
     Catch::Config config( config_data );
-    std::stringstream sstream;
-    Catch::ReporterConfig rep_config( &config, sstream );
+    StringIStream sstream;
+    Catch::ReporterConfig rep_config( &config, &sstream );
 
     // We add reporters before listeners, to check that internally they
     // get sorted properly, and listeners are called first anyway.
@@ -215,8 +226,8 @@ TEST_CASE("Multireporter updates ReporterPreferences properly",
 
     Catch::ConfigData config_data;
     Catch::Config config( config_data );
-    std::stringstream sstream;
-    Catch::ReporterConfig rep_config( &config, sstream );
+    StringIStream sstream;
+    Catch::ReporterConfig rep_config( &config, &sstream );
     Catch::MultiReporter multiReporter( &config );
 
     // Post init defaults