Two techniques are introduced for achieving semantics preserving transformations of process interconnection patterns described by algebraic parallel behaviour expressions. The semantic relation to be preserved is strong bisimulation equivalence. Convenient process network representations are identified as unique representatives of equivalence classes of parallel expressions. The first transformation technique is very simple, but can only be applied to a restricted class of expressions. The second technique is general, and achieves the desired process regrouping, whenever it exists, by inscribing the multi-arcs of the underlying process network into the binary syntax tree of a target expression pattern. The described transformation techniques have been implemented in the LOTOS integrated Tool Environment (LITE) of ESPRIT Project LotoSphere.