A high strength polyamide fiber consisting of polyamide monofilaments each having a fineness of less than 4 denier and a stress-strain curve where (a) the monofilament elongates less than 5% when subjected to an initial stress of 1.0 g/d, (b) it elongates less than 12% when subjected to a middle stress of 4.5 g/d, and (c) it elongates more than 3% over a tensile strength range from a tensile strength of at least 9.0 d/g to the tensile strength at break of the monofilament, the elongation values being measured at ambient temperature.