A process for the preparation of polyazo dyes is described which comprises(a) diazotizing a compound of the formula ##STR1## and coupling the product onto a compound of the formula ##STR2## (b) diazotizing a compound of the formula ##STR3## and coupling the product onto the product obtained according to (a); (c) diazotizing a compound of the formula ##STR4## and coupling the product onto the product obtained according to (b); (d) if desired, coupling of a further diazotized compound of the formula (3) onto the product obtained according to (c); and(e) if desired, metallizing the product obtained according to (c) or (d); and in which the symbols are as defined in claim 1. The polyazo dyes obtainable by the process are suitable for dyeing a wide range of textile and non-textile materials and, in particular, for dyeing leather.