diff --git a/include/osgDB/StreamOperator b/include/osgDB/StreamOperator
new file mode 100644
index 000000000..9498499fe
--- /dev/null
+++ b/include/osgDB/StreamOperator
@@ -0,0 +1,91 @@
+#ifndef OSGDB_STREAMOPERATOR
+#define OSGDB_STREAMOPERATOR
+
+#include <iostream>
+#include <sstream>
+#include <osgDB/DataTypes>
+
+namespace osgDB
+{
+
+class OSGDB_EXPORT OutputIterator
+{
+public:
+    OutputIterator() : _out(0) {}
+    virtual ~OutputIterator() {}
+    
+    void setStream( std::ostream* ostream ) { _out = ostream; }
+    std::ostream* getStream() { return _out; }
+    const std::ostream* getStream() const { return _out; }
+    
+    virtual bool isBinary() const = 0;
+    
+    virtual void writeBool( bool b ) = 0;
+    virtual void writeChar( char c ) = 0;
+    virtual void writeUChar( unsigned char c ) = 0;
+    virtual void writeShort( short s ) = 0;
+    virtual void writeUShort( unsigned short s ) = 0;
+    virtual void writeInt( int i ) = 0;
+    virtual void writeUInt( unsigned int i ) = 0;
+    virtual void writeLong( long l ) = 0;
+    virtual void writeULong( unsigned long l ) = 0;
+    virtual void writeFloat( float f ) = 0;
+    virtual void writeDouble( double d ) = 0;
+    virtual void writeString( const std::string& s ) = 0;
+    virtual void writeStream( std::ostream& (*fn)(std::ostream&) ) = 0;
+    virtual void writeBase( std::ios_base& (*fn)(std::ios_base&) ) = 0;
+    
+    virtual void writeGLenum( const ObjectGLenum& value ) = 0;
+    virtual void writeProperty( const ObjectProperty& prop ) = 0;
+    virtual void writeMark( const ObjectMark& mark ) = 0;
+    virtual void writeCharArray( const char* s, unsigned int size ) = 0;
+    
+protected:
+    std::ostream* _out;
+};
+
+class OSGDB_EXPORT InputIterator
+{
+public:
+    InputIterator() : _in(0), _failed(false) {}
+    virtual ~InputIterator() {}
+    
+    void setStream( std::istream* istream ) { _in = istream; }
+    std::istream* getStream() { return _in; }
+    const std::istream* getStream() const { return _in; }
+    
+    bool isFailed() const { return _failed; }
+    virtual bool isBinary() const = 0;
+    
+    virtual void readBool( bool& b ) = 0;
+    virtual void readChar( char& c ) = 0;
+    virtual void readSChar( signed char& c ) = 0;
+    virtual void readUChar( unsigned char& c ) = 0;
+    virtual void readShort( short& s ) = 0;
+    virtual void readUShort( unsigned short& s ) = 0;
+    virtual void readInt( int& i ) = 0;
+    virtual void readUInt( unsigned int& i ) = 0;
+    virtual void readLong( long& l ) = 0;
+    virtual void readULong( unsigned long& l ) = 0;
+    virtual void readFloat( float& f ) = 0;
+    virtual void readDouble( double& d ) = 0;
+    virtual void readString( std::string& s ) = 0;
+    virtual void readStream( std::istream& (*fn)(std::istream&) ) = 0;
+    virtual void readBase( std::ios_base& (*fn)(std::ios_base&) ) = 0;
+    
+    virtual void readGLenum( ObjectGLenum& value ) = 0;
+    virtual void readProperty( ObjectProperty& prop ) = 0;
+    virtual void readMark( ObjectMark& mark ) = 0;
+    virtual void readCharArray( char* s, unsigned int size ) = 0;
+    
+protected:
+    void checkStream() const
+    { if (_in->rdstate()&_in->failbit) _failed = true; }
+    
+    std::istream* _in;
+    mutable bool _failed;
+};
+
+}
+
+#endif