The (organo)gallium compounds GaCl{(SC6H4-2-PPh2)-kappa S-2,P}(2) (1), Ga{(SC6H4-2-PPh2)-kappa S-2,P[(SC6H4-2-PPh2)-kappa S}(2) (2), GaMe2{(SC6H4-2-PPh2)-kappa S-2} (3), (GaBu2)-Bu-t{(SC6H4-2-PPh2)-kappa S-2,P) (4), (GaBu)-Bu-t((SC6H4-2-PPh2)-kappa S-2,P}{(SC6H4-2-PPh2)-kappa S) (5), [GaMe2{(mu(2)-SC6H4-2-AsPh2)-kappa S}](2) (6), and (GaBu)-Bu-t{(SC6H4-2-AsPh2)-kappa S-2,As}{(SC6H4-2-AsPh2)-kappa S} (7) were obtained from the reaction of 2-EPh2C6H4SH (E = P (PSH), As (AsSH)) with GaCl3 (1, 2) or GaR3 (R = Me, Bu-t; 3-7) in different molar ratios and under different reaction conditions. Compound 2 was also obtained from Li(PS) and GaCl3 (3.5:1). While a monomeric structure with a chelating phosphinoarylthiolato ligand is observed in GaMe2{SC6H4-2-PPh2)-kappa S-2,P} (3), a dimeric arsinoarylthiolato-bridged complex [GaMe2[(mu(2)-SC6H4-2-AsPh2)-kappa S}](2) (6) is obtained with the corresponding Ass(-) ligand. B3LYP/6-31G(d) calculations show that although the dimer is thermodynamically favored for both ligands, the formation of 3 is due to the combination of higher stability of the chelate compared with the monodentate phosphorus ligand and a higher barrier for the ring opening of the PS- than of the AsS- chelate.