Disclosed are basic azo dyes, free from sulphonic acid groups, and of formula, ##STR1## in which Q signifies an unsubstituted or substituted phenyl or naphthyl radical,R.sub.1 signifies hydrogen, unsubstituted or substituted C.sub.1-4 alkyl, phenyl or cyclohexyl,Z signifies a ring forming residue,R.sub.4 signifies optionally substituted alkyl, alkenyl, alkoxy or cycloalkyl,K signifies a coupling component,A.crclbar. signifies an anion, andx signifies 1, 2 or 3.The dyes are useful for dyeing and printing textiles of polymers and copolymers of acrylonitrile and dicyanoethylene as well as synthetic polyamides and polyesters that have been modified to contain acid groups. The dyeings are level and exhibit good fastness to light, wet treatments, perspiration, sublimation, pressing and dry cleaning.