Invisible labor is an intrinsic part of the modern workplace, and includes labor that is undervalued or unrecognized such as creating collaborative atmospheres. Open source software (OSS) is software that is viewable, editable and shareable by anyone with internet access. Contributors are mostly volunteers, who participate for personal edification and because they believe in the spirit of OSS rather than for employment. Volunteerism often leads to high personnel turnover, poor maintenance and inconsistent project management. This in turn, leads to a difficulty with sustainability long term. We believe that the key to sustainable management is the invisible labor that occurs behind the scenes. It is unclear how OSS contributors think about the invisible labor they perform or how that affects OSS sustainability. We interviewed OSS contributors and asked them about their invisible labor contributions, leadership departure, membership turnover and sustainability. We found that invisible labor is responsible for good leadership, reducing contributor turnover, and creating legitimacy for the project as an organization.