Abstract: The present invention relates to a novel process for the production of a copolyamide comprising a polymerization product of hexamethylene diamine, adipic acid and terephthalic acid. A process for the production of a copolyamide comprising less than 50 mol % of units of hexamethylene terephthalamide may include (a) introducing an aqueous solvent and the monomers adipic acid, terephthalic acid and hexamethylene diamine, or salts thereof, into an evaporator to obtain a mixture; (b) concentrating the mixture obtained in step (a) in the evaporator by evaporation of at least part of the solvent, to obtain a concentrated mixture; (c) transferring the concentrated mixture obtained in step (b) into an autoclave; (d) polymerizing the monomers in the autoclave at a pressure of at least 1.