Does the intensification of labour increase the rate of exploitation? Does it produce absolute surplus value or relative surplus value? This paper develops a framework to answer these questions by incorporating intensity of labour in the widely-used linear model of production, both in its one and two department forms. We show, first, that an intensification of labour always leads to an increase in the rate of exploitation, and second, that the increase in the rate of exploitation takes the form of the production of absolute surplus value in all realistic situations. We also highlight, in the case of any model with more than one industry or sector, an interesting difference in short run and long run changes in the rate and form of surplus value.