This paper studies the gains to productivity from joint work of individuals with different levels of human capital within a firm. The analysis is based on a unique panel data-set which documents partners, investments and investment outcomes of Venture Capital firms in California during 1979-2002. I find that more successful venture capitalists recruit more new partners and that this effect increases when there is growth in the aggregate number of Venture Capital investments. Based on these findings I develop and estimate a structural model which quantifies the increase in venture capitalists' productivity through skill leverage in the firm. I find that joint work increased productivity of experienced and inexperienced partners by 8%.