Crystals of the 2,6-dichlorobenzoyl ester of C.I. Disperse Yellow 23 and C.I. Disperse Orange 29 were grown from chloroform, and cell dimensions were determined by a least-squares fit. Crystals of both esters were found to exist in the monoclinic space group P2(1)/C. The structures of these dyes possessed the anti conformation, unlike that of underivatized C.I. Disperse Orange 29, but the same as that reported for 4-phenylazoazobenzene. (C) 1997 Elsevier Science Ltd.