The invention comprises azo dyestuffs of formula R1-NH-CO-CH=CH-CH=CH-CO-NH-R1 in which one or two hydrogen atoms of the radical -CH=CH-CH=CH- may be substituted by a halogen atom or an alkyl group, and R1-NH- is a radical of an aromatic amine containing one or more azo groups and a sufficient number of water-solubilizing groups to make the dyestuff water-soluble; and also mixtures comprising two or more dyestuffs of the above formula and one or more azo dyestuffs of formula R11-NH-CO-CH=CH-CH=CH-CO-NH-R111 which are defined as above except that R11-NH-and R111-NH- are radicals of different aromatic amines. The dyestuffs may contain metal atoms in complex linkage, copper and nickel being preferred. The dyestuffs are prepared by condensing with 1 mol of a butadiene - 1 : 4 - dicarboxylic acid halide or a derivative thereof substituted by a halogen atom or an alkyl group; (I) 2 mols of one or more aromatic amines having one or more azo groups which may be protected by metal atoms linked by a complex linkage; (II) 2 mols of one or more aromatic amines having, in addition to the amino group which is to be condensed, a diazotizable amino group, diazotizing the diazotizable amino group of the resultant amino compound and uniting each azo group with a coupling component; (III) 2 mols of one or more aromatic amines having in addition to the amino group which is to be condensed, a nitro group or easily saponifiable acylamino group, converting these groups in the condensation product by reduction or saponification to diazotizable amino groups and proceeding as in (II); (IV) 2 mols of one or more aromatic amines having a carbon atom which is capable of coupling with a diazo compound, and coupling the resultant condensation product with 2 mols of one or more diazo compounds; (V) a mixture of 1 mol of an aromatic amine having a carbon atom capable of coupling with a diazo compound and 1 mol of another aromatic amine having in addition to the amino group which is to be condensed a diazotizable amino group or a nitro or easily saponifiable acylamino group, converting any nitro or acylamino group present in the condensation product to an amino group by reduction or saponification, coupling the resultant material with 1 mol of a diazo compound, diazotizing the product of coupling and further coupling the diazotized compound with 1 mol of a coupling component. In each case the starting materials are chosen so that a sufficient number of water-solubilizing groups are present to give water colubility. The dyestuffs obtained by the above processes which contain metallizable groupings may be metallized in substance or on the fibre by known methods. The dyestuffs dye cotton and regenerated cellulose fibres in yellow, red, green, blue and grey shades. They also dye leather and animal and synthetic polyamide fibres. In examples: (1) Butadiene-1 : 5 - dicarboxylic acid chloride in condensed with the following aminoazo compounds and mixtures:-2 - aminonaphthalene - 4:8 - disulphonic acid --> 1 - amino - 3 - [acetylaminobenzene, 2 - aminonaphthalene - 4:8-disulphonic acid --> 1-amino-2 - methybenzene and 2 - aminonaphthalene - 6:8 - disulphonic acid --> 1 - amino - 3 - ethylbenzene, 1 - amononaphthalene-3:6 - disulphonic acid --> 1 - amino - 3 - formylaminobenzene and 2 - aminonaphthalene-5:7 - disulphonic acid --> 1-amino-2:5 - dimethylbenzene, 2 - amino naphthalene - 4:8 - disulphonic acid --> 1 - amino - 2:5 - diethoxybenzene, 3 - aminopyrene - 5:8 - and - 5:10 - disulphonic acids --> 1 - amino - 3 - methylbenzene, 4-amino - 1:11 - azobenzene 3:41 - disulphonic acid --> 1 - amino - 3 - methylbenzene, 4 - amino - 1:11 - azobenzene - 31:41-disulphonic acid --> 1-amino-2-methoxy-5-methylbenzene and 2-aminonaphthalene-4:8-disulphonic acid --> 1-amino-3-methoxybenzene, 2-aminonaphthalene - 6 : 8 - disulphonic acid --> 1-amino-3-methylbenzene --> 1-amino-2-methoxy - 5 - methylbenzene and 2 - aminonaphthalene - 6 : 8 - disulphonic acid --> 1-amino-3-acetylaminobenzene --> 1 - amino - 3 - methylbenzene, 1 - aminobenzene - 4 - sulphonic acid --> 1 - aminonaphthalene - 6 - sulphonic acid --> 1 - amino - 3 - methylbenzene and 4 - amino - 1 : 11 - azobenzene - 3 : 41 - disulphonic acid --> 1 - amino - 3 - methylbenzene, 3 - aminopyrene - 4 - sulphonic acid --> 1 - amino - 3 - methylbenzene and 2 - aminonaphthalene - 4 : 8 - disulphonic acid --> 1 - amino - 2 - methoxy - 5 - methylbenzene, 4 - amino - 1 : 11 - azobenzene - 41 - sulphonic acid and 2 - aminonapthalene - 6 : 8 - disulphonic acid --> 1 - amino - 3 - methylbenzene, 2 - aminonaphthalene - 4 : 8 - disulphonic acid --> 1 - amino - 3 - acetylaminobenzene and aminobenzene --> 1 - aminonaphthalene - 6 - sulphonic acid --> 1 - aminonaphthalene - 6 - sulphonic acid --> 2 - amino - 8 - hydroxynaphthalene - 6 - sulphonic acid, 2 - acetylamino - 4 - amino - 41 - hydroxy - 1 : 11 - azobenzene - 31 - carboxylic acid, 1 - carboxy - 2 - aminobenzene - 4 - sulphonic acid --> 1 - (31 - amino) - phenyl - 3 - methyl - 5 - pyrazolone and 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - (41 - amino) - phenyl - 3 - methyl - 5 - pyrazolone, 1 - hydroxy - 2 - (41 - amino) - benzoylamino - 6 - carboxybenzene - 4 - sulphonic acid --> 1 - amino - 3 - methylbenzene and 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - (41 - amino) - phenyl - 3 - methyl - 5 - pyrazolone, 2 - amino - 5 - nitrobenzene - 1 - carboxylic acid --> 1 - phenyl - 3 - methyl - 5 - pyrazolone - 31 - sulphonic acid or 1 - hydroxynaphthalene - 3 : 6 - disulphonic acid and reduction, 1 - amino - 2 - hydroxy - 6 - nitronaphthalene - 4 - sulphonic acid --> 1 - phenyl - 3 - methyl - 5 - pyrazolone - 31 - sulphonic acid and reduction, 1 - hydroxy - 4 - (41 - amino) - benzoylamino - 6 - carboxybenzene - 2 - sulphonic acid --> 1 - amino - 3 - methylbenzene and 1 - hydroxy - 4 - amino - 6 - carboxybenzene - 4 - sulphonic acid --> 1 - amino - 3 - acetylamino - benzene, 4 - amino - 41 - hydroxy - 1 : 11 - azobenzene - 3 - 31 - carboxylic acid and 1 - hydroxy - 4 - amino - 6 - 6 - carboxybenzene - 2 - sulphonic acid --> 1 - amino - 3 - methylbenzene, 1 - hydroxy - 4 - amino - 6 - carboxybenzene - 2 - sulphonic acid --> 1 - amino - 3 - acetylaminobenzene and 1 - hydroxy - 2 - (41 - amino) - benzoylamino - 6 - carboxybenzene - 4 - sulphonic acid --> 1 - amino - 3 - methylbenzene --> 1 - amino - 3 - methylbenzene, 1 - hydroxy - 2 - amino - 6 - chlorobenzene - 5 - sulphonic acid --> 2 - amino - 5 - hydroxynaphthalene - 7 - sulphonic acid and 1 - hydroxy - 2 - amino - 6 - chlorobenzene - 4 - sulphonic acid --> 1 - (411 - amino - 11 : 111 - stilbenyl - 41) - 3 - methyl - 5 - pyrazolone - 21 : 211 - disulphonic acid, o - aminophenoxyacetic acid --> 2 - amino - 5 - hydroxynaphthalene - 7 - sulphonic acid and copper complex from 1 - hydroxy - 2 - aminobenzene - 4 : 6 - disulphonic acid --> 2 - amino - 5 - hydroxynaphthalene - 7 - sulphonic acid, 1 - methoxy - 2 - amino - 5 - nitrobenzene --> 1 : 8 - dihydroxynaphthalene - 3 : 6 - disulphonic acid and reduction, 2 - aminobenzene - 1 - carboxylic acid --> 1 - (411 - amino - 11 : 111 - stilbenyl - 41) - 3 - methyl - 5 - pyrazolone - 21 : 211 - disulphonic acid --> 1 - amino - 3 - methylbenzene and 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - (411 - amino - 11 : 111 - stilbenyl - 41) - 3 - methyl - 5 - pyrazolone - 21 : 211 - disulphonic acid --> 1 - amino - 3 - methylbenzene, copper complex from 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - amino - 4 - acetoacetylaminobenzene and 1 - hydroxy - 2 - (41 - amino) - benzoylamino - 6 - carboxybenzene - 4 - sulphonic acid --> 1 - amino - 3 - propionylaminobenzene, 1 - carboxy - 2 - aminobenzene - 5 - sulphonamide --> 1 - (41 - amino) - phenyl - 3 - methyl - 5 - pyrazolone and 4 - amino - 31 - carboxy - 41 - hydroxy - 1 : 11 - azobenzene - 51 - sulphonic acid, 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid methylamide --> 1 - (411 - amino - 11 : 11 - stilbenyl - 41) - 3 - methyl - 5 - pyrazolone - 21 : 211 - disulphonic acid, copper complex from 3 : 31 - dimethoxy - 4 : 41 - diamino - 1 : 11 - diphenyl --> 1 - amino - 8 - hydroxynaphthalene - 3 : 6 - disulphonic acid and copper complex from 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - (411 - amino - 11 : 111 - stilbenyl - 41) - 3 - methyl - 5 - pyrozolone - 21 : 211 - disulphonic acid, 1 - hydroxy - 2 - (41 - amino) - benzoylamino - 6 - carboxybenzene - 4 - sulphonic acid --> 1 - amino - 3 - methylbenzene; 2 - methylbutadiene - 1 : 4 - dicarboxylic acid chloride is condensed with 1 - carboxy - 2 - aminobenzene4 - sulphonic acid --> 1 - (41 - amino) - phenyl - 3 - methyl - 5 - pyrazolone; 1 : 4 - dichlorobutadiene - 1 : 4 - dicarboxylic acid chloride is condensed with 1 - carboxy - 2 - aminobenzene - 5 - sulphonic acid --> 1 - (411 - amino - 11 : 111 - stilbenyl - 41) - 3 - methy - 5 - pyrazolone - 21 : 211 - disulphonic acid: (2) 4 : 41 - diamino - 1 : 11 - diphenyl - 3 - sulphonic acid is condensed with butadiene - 1 : 4 - dicarboxylic acid chloride to give butadiene - 1 : 4 - dicarboxylic acid - [311 - sulpho - 411 - amino - 11 : 111 - diphenyl - (41)] - amide which is tetrazotized and coupled with 1 - acetoacetylamino - 4 - hydroxybenzene - 3 - carboxylic acid: (3) 2 mols of 2 - nitro - 5 - aminobenzene - 1 - carboxylic acid are condensed with 1 mol of butadiene - 1 : 4 - dicarboxylic acid chloride, the nitro groups reduced to amino and the resultant diamine tetrazotized and coupled with 1 - phenyl - 3 - methyl - 5 - pyrazolone - 41 - sulphonic acid: (4) 2 - amino - 5 - hydroxynaphthalene - 7 - sulphonic acid is reacted with butadiene - 1 : 4 - dicarboxylic acid chloride to give butadiene - 1 : 4 - dicarboxylic acid - [51 - hydroxy - 71 - sulphonaphthyl - (21)] - amide which is coupled with diazo compounds from the following amines, 1 - hydroxy - 2 - (41 - amino) - benzoylamino - 6 - ca