Given the collaborative nature of software development, a robust team is a necessity for project success in both commercial and open source environments. That is, in the event of developers’ absence due to various reasons, how could it potentially disrupt a team’s routine operations? This article offers an automatic approach to intuitively visualize development team hierarchy, quantify overall team robustness, and identify the point (developers) of risk for team robustness. An investigation of six Apache open source projects has shown its effectiveness. This article is part of a special issue on Actionable Analytics for Software Engineering.