Metal complex compounds of primary disazo dyes are made by treating with agents yielding metals monosulphonated disazo dyes of the type R --> R1 \sM R, in which both R's = aromatic monoamines, of which one contains an SO3H group and at least one contains a group capable of forming a metal complex and R1 = an unsulphonated aryl derivative containing two OH groups. The monazo dye R --> R1 may also be metallized and then coupled to form the disazo dye; the latter may be further treated with an agent yielding metal (cf. Specification 297,003, [Class 2 (iii)]). Metals specified are chromium, copper, iron, aluminium, cobalt, nickel, manganese, zinc, vanadium and titanium. The treatment with the agent yielding metal may be conducted simultaneously with the production of the dyestuff and in many cases on the fibre or in the dye-bath. More than one metal may be used in the various processes. The metal compounds dye wool and silk and are particularly suitable for dyeing leather tanned in any desired manner. In examples the following dyes are described: (1) 4-nitro-2-aminophenol --> resorcinol (iron compound) \sM sulphanilic acid (greenish yellow-brown on vegetable tanned leather); (2) 4-nitro-2-aminophenol --> resorcinol (manganese compound) \sM 4-nitro-2-aminophenol-6-sulphonic acid treated with ferric chloride in acid solution (olive dark brown); (3) 4-chloro-2-aminophenol --> resorcinol (iron compound) \sM 4-nitro-2-aminophenol-6-sulphonic acid treated with copper sulphate in acid solution (red brown on chrometanned leather); (4) 4-nitro-2-aminophenol --> resorcinol (iron compound) \sM 4-chloro-2-aminophenol-6-sulphonic acid treated with chromium sulphate; (5) 4-nitro-2-aminophenol --> resorcinol (cobalt compound) \sM 4-chloro-2-aminophenol-6-sulphonic acid treated with copper sulphate, tartaric acid and caustic soda (Russia leather red); (6) 4-nitro-2-aminophenol --> resorcinol containing ferric chloride and caustic soda and heated to form the iron compound \sM 6 - nitro - 2 - aminophenol - 4 - sulphonic acid treated with copper sulphate and ferric chloride (reddish brown); (7) 4-nitro-2-aminophenol --> resorcinol containing ferric chloride and caustic soda \sM 4-nitro-2-aminophenol-6-sulphonic acid heated with a suspension of ferric hydroxide (olive brown); (8) 4 : 6-dinitro-2-aminophenol --> resorcinol \sM 4-sulpho-2-aminobenzoic acid treated with ferric chloride, (9) 4-nitro-2-aminophenol --> resorcinol \sM 4 - nitro - 2 - aminophenol - 6 - sulphonic acid heated with ferric chloride and copper sulphate (reddish brown); (10) 4-chloro-2-aminophenol-6-sulphonic acid --> resorcinol \sM 4-chloro-2-aminophenol heated with a solution of cobalt sulphate, zinc sulphate, aluminium sulphate, tartaric acid and caustic soda (bordeaux red); (11) a mixture of diazotized 5 - nitro - 2 - aminophenol and 6 - nitro-2 - aminophenol - 4 - sulphonic acid coupled with resorcinol containing copper sulphate, nickel sulphate and caustic soda and the mixture heated (bordeaux red); three or more different diazo components may be similarly used; (12) similar to (11) using a mixture of diazotized 4-nitro-2-aminophenol and its 6-sulphonic acid and resorcinol, ferric chloride and copper sulphate (olive dark brown); (13) a mixture of diazotized 4 - sulphamino - 2 - aminophenol and 4 - chloro - 2 - aminophenol - 6 - sulphonic acid coupled with resorcinol and the product treated with chromium and copper sulphates (bluish wine red); (14) a diazotized mixture of 5 - nitro - 2 - aminophenol and 4 - chloro - 2 - aminophenol-6-sulphonic acid coupled with resorcinol treated with cobalt sulphate, tartaric acid and caustic soda (bluish bordeaux red). In examples of dyeing (15) neutralized chrome leather is dyed the manganese /iron compound of 4 - nitro - 2 - aminophenol --> resorcinol \sM 4 - nitro - 2 - aminophenol - 6 - sulphonic acid (full olive dark brown); (16) vegetable tanned leather is dyed with the cobalt /copper compound of 4-nitro-2-aminophenol --> resorcinol \sM 4 - chloro - 2 - aminophenol - 6 - sulphonic acid (Russia leather red). Other components specified are resorcinol-4- or 5- carboxylic acids, a dioxynaphthalene or a nitro-, alkyl or halogen derivative thereof; amines of the benzene and naphthalene series, including those containing o-hydroxy-, carboxy- and alkoxy groups, or which contain the salicylic group as well as the sulphonic, nitro, alkyl and halogen derivatives. Alternative components are specified in the examples including in addition to those above sulphanilic acid, chlor-sulphoaminobenzoic acids, 6-nitro-4-chlor-2-aminophenol and 6 - chlor - 4 - nitro - 2 - aminophenol. Alternative metal compounds are also specified in the examples. Specifications 297,331, [Class 2 (iii)], and 343,014 also are referred to.