Abstract: The present invention provides a process for producing polyamides, which comprises a) providing a monomer composition comprising at least one lactam or at least one aminocarbonitrile and/or oligomers of these monomers, b) reacting the monomer composition provided in step a) in a hydrolytic polymerization at elevated temperature in the presence of water to obtain a reaction product comprising polyamide, water, unconverted monomers and oligomers, c) the reaction product obtained in step b) being fed into at least one kneader (3) and subjected to a postpolymerization, d) optionally forming the reaction product obtained in step c) to obtain polyamide particles, e) optionally treating the reaction product obtained in step c) or the polyamide particles obtained in step d) with at least one extractant.