Hi, <boost/shared_ptr.hpp> contains the following in the public section of the class definition (reformatted): // Tasteless as this may seem, making all members public // allows member templates to work in the absence of member // template friends. (Matthew Langston) #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS private: template<class Y> friend class shared_ptr; template<class Y> friend class weak_ptr; #endif T * px; // contained pointer detail::shared_count pn; // reference counter This has become a pretty common technique, I believe. I certainly use it a lot, at any rate. I'd like to suggest two macros which would allow code like the above to be simplified as follows: BOOST_PRIVATE: BOOST_BEFRIEND_TEMPLATE(shared_ptr, Y, 1) BOOST_BEFRIEND_TEMPLATE(weak_ptr, Y, 1) T * px; // contained pointer detail::shared_count pn; // reference counter Here BOOST_PRIVATE would expand to "private" for compilers that support template friends and to "public" otherwise; BOOST_BEFRIEND_TEMPLATE would expand to a template friend declaration where supported, and to nothing otherwise. It might be desirable to have two macros BOOST_BEFRIEND_TEMPLATE_CLASS and BOOST_BEFRIEND_TEMPLATE_STRUCT to avoid compiler warnings. Jonathan