QSharedData is for sharing data between objects that are implicitly shared (copy-on-write) within a process. Sharing across processes is a QSharedMemory task. You can create() a chunk of memory to contain your shared data structure. Both processes can retrieve/store information in with appropriate use of lock(), unlock(), data(), and constData(). Passing a pointer between processes strikes me as a no-no though: the memory pointed to is part of the sending process and should not generally be accessible from another process.