The effect of alloying the parent Gd(5)Si(2)Ge(2) (GSG) compound with 3d (Co and Mn) and p (Ga and B) elements have been investigated. The alloying mechanism causes simultaneous substitution of the nonmagnetic Si and Ge atoms from the (Si+Ge) sub lattice in equal amounts. X-ray powder diffraction, magnetization vs. temperature and magnetization vs applied magnetic field at constant temperature data were collected. Curie temperatures were determined from M(T) measurements and the magnetocaloric characterization was made by plotting the magnetic entropy change values against temperature from M(H) measurements. The magnetic characteristics of the parent compound were significantly modified by alloying with Co.