The interactions of dichlorotris(triphenylphosphine)ruthenium(II), RuCl2(PPh3)3, with various reagents have been studied and the resulting complexes characterised by i.r. and n.m.r. spectroscopy. The new complexes comprise those of nitriles, RuCl2(RCN)2(PPh3)2, amines, RuCl2(amine)2(PPh3)2, β-diketonates, Ru(β-diket)2(PPh3)2, carboxylates, Ru(OCOR)2(PPh3)2, the halogen bridged dimer [RuCl2(PPh3)2]2 and its acetone solvate and chloro-π-cyclopentadienylbis(triphenylphosphine)ruthenium(II).