Hi, I'm rather new to shared_ptr and I'm not very experienced in programmer with C++ but have to do it anyway. My problem is this: I have 3 .cpp files, e.g. Master.cpp, Client.cpp and Satellite.cpp. Originally, Master.cpp is the only .cpp file, and uses auto_ptr to enable writing and reading from an interface. Like this: { .... auto_ptr<FtInterface> fti (ftGetIfFromFactory(device, connection)); fti->getIfInfo(ii); IfOutputs out; // to set interface outputs (ctor clears everything to 0) IfInputs inp; // to be read from interface fti->writeAndReadAllData(out, inp); ... } This works well with every action taking place in this file. Now, as said I have those 3 .cpp files. Master.cpp sends an argument to Client.cpp and Client.cpp sends it to Satellite.cpp. Satellite.cpp reads from the interface, and sends it back via Client.cpp to Master.cpp. I can't use auto_ptr with this and from the Boost-documentation I can't figure out exactly how to use shared_ptr for this. Can somebody please help me out? I hope I explained my problem clear enough. Thank you for helping out. H.