Following the indium triorganyls and their adducts with Lewis bases in Section 1, the broad field of compounds of the general type R ln- n 3 n (n = 1, 2) is treated in sections 2 to 9; Ionic species, predominantly (R lnX -n)-compounds (n = 1 to 4), close the series of trivalent n 4 organoindium compounds and are collected in Section 11.