Centrioles are essential for forming cilia, flagella, and centrosomes and are thus critical for a range of fundamental cellular processes. Despite their importance, the mechanisms governing centriole biogenesis remain incompletely understood. We performed a high-content genome-wide small-interfering-RNA-based screen to identify genes regulating centriole formation in human cells. We designed an algorithm to automatically detect GFP-Centrin foci that, combined with subsequent manual analysis, allowed us to identify 44 genes required for centriole formation and 32 genes needed for restricting centriole number. Detailed follow-up characterization uncovered that the C2 domain protein C2CD3 is required for distal centriole formation and suggests that it functions in the basal body to template primary cilia. Moreover, we found that the E3 ubiquitin ligase TRIM37 prevents centriole reduplication events. We developed a dynamic web interface containing all images and numerical features as a powerful resource to investigate facets of centrosome biology.