I have four easy questions regarding boost::shared_ptr: 1.) How do I pass a boost::shared_ptr to a function - via value or reference? void ByValue( boost::shared_ptr<Foo> pFoo ); void ByReference( boost::shared_ptr<Foo>& rFooPtr ); 2.) When passing a raw pointee to a function you can declare the pointee const. How do I pass a const boost::shared_ptr? void ConstRaw( const Foo* pFoo ); void ConstSharedPtr( ??? ); 3.) Does anything speak against passing a reference to a factory function instead of returning the boost::shared_ptr? boost::shared_ptr<Foo> Create( void ) { return boost::shared_ptr<Foo>( new Foo ); } bool Create( boost::shared_ptr<Foo>& foo ) { // Make some validations and return false on error. // ... // Everyting is ok. Reset the pointee and return a success foo.reset( new Foo ); return true; } 4.) Can I test a boost::shared_ptr against NULL like a raw pointee? Regards, -Dirk