The supply of labour is traditionally analysed within the framework of static neoclassical demand theory. This static model of labour supply is well known and has received a considerable amount of econometric attention. A recent survey by Heckman, Killingsworth and McCurdy (1981) provides both an excellent guide to this literature and an extensive bibliography. Developments to the static model have for the most part concentrated on the econometric methodology that is required when the model is extended to incorporate household, as opposed to individual, decision making (1), the joint determination of commodity demands and labour supply (2), and non linearities that arise in the budget constraint due to non linear taxes, fixed costs, rationing, etc. (3).