Interaction of cis-Ptdppp(p-C6H4CN)(2) or cis-Ptdppp(p-C2C6H4N)(2) with cis-ML(2)(OSO2CF3)(2) (M = Pt Or Pd; L = PEt(3) or L(2) = dppp) in CH2Cl2 Or acetone, at room temperature, results in mixed, neutral-charged cyclic tetranuclear, Pt-Pt or Pt-Pd macrocyclic complexes in 90-99% yields via self-assembly. All tetramers are microcrystalline air- and water-stable solids with decomposition points > 170 OC. The benzonitrile based macrocycles can be disassembled in solution with 4,4’-bipyridine, while the 4-ethynylpyridine systems are more stable toward a variety of guests. The 4-ethynylpyridine tetramers display host-guest chemistry with silver triflate via the "pi-tweezer effect". The X-ray crystal structure as well as FABMS, including isotope patterns, are reported for the tetranuclear macrocycle cyclobis[[cis-Pt(dppp)(4-ethynylpyridine)(2)][cis-Pd2+(PEt(3))(2)2(-)OSO(2)CF(3)]] (14).