As software development cycles become shorter and shorter, while software complexity increases and IT budgets stagnate, many companies are looking for new ways of acquiring and sourcing knowledge outside their boundaries. One promising solution to aggregate know-how and manage large distributed teams in software development is crowdsourcing. This paper analyzes the existing body of knowledge regarding crowdsourcing in software development. As a result, we propose a fundamental framework with five dimensions to structure the existing insights of crowdsourcing in the context of software development and to derive a research agenda to guide further research.