Abstract: Amorphous (co)polyamides are polycondensed from aromatic dicarboxylic acid(s), e.g., isophthalic acid and/or terephthalic acid, and from aliphatic diamine(s), e.g., hexamethylenediamine, by preparing two unbalanced prepolymers of low viscosity, one containing excess COOH endgroups and the other containing excess NH.sub.2 endgroups, and then, in a second stage, the two unbalanced prepolymers are mixed in given proportions and their postcondensation is carried out in the molten state in a vented extruder including one or more screws; the amorphous (co)polyamides thus prepared are perfectly transparent and can be easily injection molded into useful shaped articles endowed with good properties, especially in respect of multiaxial impact.