Structure-property relations have been studied in the following systems: (a) perovskite type BaPbl-xCuxO3 and Ba1-xLaxPbO3 and (b) K2NiF4 type Ba2Pb1-xMxO4 (M = Bi, Sb) and Ba2Pb1-xBixO4-yFy. In the case of BaPb1-xCuxO3, an orthorhombic to pseudo-cubic structural transition is observed at x = 0.3 and the samples remained metallic. A similar behaviour is observed also in Ba1-xLaxPbO3. In both systems, the metallic character of BaPbO3 was found to decrease with substitution. No evidence for superconductivity is observed in any of the compositions. However, a non-reproducible superconducting like transition has been noticed in a nominal, multiphasic Ba-2(Pb0.75Bi0.25)O3F composition at around 40 K.