While the management of projects is rapidly gaining importance in the current fast pace economy, there is a growing dissatisfaction with its theoretical underpinnings. Rooted in an exploratory micro-analysis of the practices of 86 project managers, our study demonstrates that project managers engage in 10 core practices, which together imply that managing projects 1) is only partly about planning and scheduling, 2) is locally situated in specific types of projects, 3) is an activity aimed at a continuous recoupling of diverse practices, and 4) is shaped by project contexts, which act as temporary points of intersection for social practice. Together, we propose these practices form a set of building blocks for a practice-perspective of project-based organization, presenting an alternative to the theoretical paradigm currently dominating the field.