We propose a theory of firm production that requires diverse inputs. We show that in a competitive labor market, firms differ in their skill composition. Organizations with higher total factor productivity (TFP) are larger and hire from a broader range of skills. Technological progress leads to...

Just like perfect (frictionless) matching models, a search model is proposed that is characterized by bilateral search and vertical heterogeneity. It allows for a generally specified utility function. The equilibrium allocation is unique and exists in iterated strict dominance. The model is...