ABSTRACT:In confronting problems of employment and unemployment, students of the labour market, and economists in general have focused mainly on the determination of the level of such variables.Much less attention has been paid to such questions as: how many persons have entered the area of employment and the labour force in various time periods, and how many have exited; their sex and age distribution; and the determinants of the level and structure of flows amongst the various labour market conditions. Yet it appears superfluous to underscore the relevance of such questions. To illustrate, suffice it to recall that in Italy, the present level of employment is essentially the same today as it was in 1961‘; but this has not prevented whole generations of young people from 'stably’entering the employment area, albeit with varying degrees of difficulty in different periods.As for the numerous statistical surveys of labour market flows in a range of countries, and as for the works of job search theorists2, it should be observed that such surveys and analyses essentially concern conjunctural phenomena. Consequently, these authors have paid no attention to the distinction between short‐run turnover and generational turnover, or to the extremely singular characteristics of the statistical data on flows. An attempt to construct labour market models that present an integrated version of the 'structural’aspects of the market in terms of stock and flows is therefore lacking.The present study sets forth various objectives and is divided into two parts.In the first, an analysis of several controversial terminological aspects of the concepts of stock and flow is presented, and an attempt is made to point out those theoretical structures which have been responsible for the long‐prevailing neglect of the labour market flows, particularly long‐run flows. Then the problem of defining the concepts of short‐run and generational turnover will be confronted in light of an analysis of the statistical methods used in the surveys; finally, a methodology for measuring generational flows is proposed.In the second part of the paper a model based on generational flows, as previously defined, will be presented together with a computational procedure capable to produce long run estimates of alternative scenarios of labour demand and supply and of the structure of employment by sex and age. A brief summary of some of the empirical results obtained applying our model and forecasting procedure to the Italian labour market will also be discussed in the final part