Endocyclic homodinuclear complexation and endo/exocydic heteronuclear networking of calix[4]-bis-monothiacrown-5 (L) are reported. First, dipotassium(I) and disilver(I) complexes of L were isolated and their solid state structures characterized. To probe the complexation behavior for these same systems in solution, the competition between potassium(I) and silver(I) for L was monitored by H-1 NMR Potassium(1) showed a higher affinity to L than silver(l) both in the solid and solution states. The reaction of L with KI in the presence of HgI2 afforded a two-dimensional coordination polymer with the endocyclic dipotassium(I) complex linked by an exocyclic mercury(II) iodide cluster backbone.