Hi, Some collective operations are not implemented in Boost.MPI, namely Scatterv and Gatherv. Probably there is a great reason and i don't know. Something related to Boost.Serialization or the "skeleton and content" approach? (due to memory offsets, displacements, etc.) Can i write some code to you? I did check scatter.hpp and maybe is easy to implement by analogy. Best Regards, Júlio.