We address an assembly problem, motivated by flat panel display manufacturing, where the quality (or performance) of the final product depends upon characteristics of the components to be assembled, which are not constant from component to component. We analyze the tradeoff between the increase in the potential value of products gained by putting off the "mating" of components exhibiting various characteristic "types," and the inventory costs caused by this delay in mating. We formulate this dynamic type mating problem as a Markov Decision Process and characterize the structure of the optimal policy for special cases. We then present a heuristic policy for a more general case and compare its performance against the optimal policy. Computational results indicate that the heuristic is effective for a wide variety of cases.