The current knowledge about azides of the heavier Group 13 elements is reviewed. Only neutral compounds of the general formula R3-xM(N-3)(x)(D)(y) and MN3 (M = Al, Ga, In, Tl; R = organic or inorganic substituent; D = neutral donor; y = 0-3) are taken into account. The syntheses of Group 13 azides of the formal oxidation number +III can either be achieved by salt metathesis, a bond metathesis, or substitution reactions. The synthesis, structures, properties, and applications of mono-, di-, and triazides including inter- and intramolecular donor-stabilized compounds are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.