The strength of wet-spun poly(vinyl alcohol) (pva) fibres is given as function of bath-stretching, wet-stretching and hot-stretching. In the two equations derived for strength of wet-stretching and hot-stretching the complex influence of the bath-stretching and hot-stretching is demonstrated. The bath-stretching is connected with a pure orientation effect and the residence time in the coagulating bath which is a measure for the ‘freshness’ of the fibre. The hot-stretching can be separated in a pure orientation effect and a crystallization effect. Fibres of the pva, used in the experiments, were soluble in boiling water. After shrinkage of the fibres at temperatures near the temperature of hot-stretching, the dissolution temperature can be raised. Insoluble pva fibres were prepared after removing most of the bulky residual ester groups.