[영문]The aim of this article is to define the factors which determine seniors' decisions to continue to participate in the labour market in Argentina. An option value model is developed. This model is used to produce estimates based on micro-data drawn from household surveys. These indicate the relative importance of the impact of conditions governing eligibility for benefits on decisions to remain actively employed. Work history is found to be the main factor in such decisions. Inadequacy of social security benefits and accumulated human capital also create incentives for economic participation in old age. On the basis of these findings, compensatory policy adjustments, to improve coverage, increase benefit levels and improve employment conditions for seniors, are proposed.