ABSTRACT: An organizational strategy to deal with software development has been developed in the market. Organizations openly release source code and hope to attract volunteers to improve their projects (software). Examples of organizations that have used this strategy include: a) IBM released Eclipse, which is now an independent entity; b) SAP provides the Netweaver environment to its clients so they can develop SAP applications; and c) Mozilla released its email client Thunderbird and already enjoys a comfortable position within the open source community. This research proposes a theory to explain constructs of interest for organizations that adopt such a "going-open" strategy. It is proposed that attractiveness of these projects is a central tenet, leading to activeness, efficiency, likelihood of task completion, and time for task completion of these communities of open source projects, though not linearly, as task complexity is believed to moderate the links between them. It is also proposed that activeness, efficiency, likelihood of task completion, and time for task completion mediate the relationship between attractiveness and software quality. Additionally, the model proposes that four open software projects' characteristics (license type, intended audience, type of project, and project's life-cycle stage) influence their level of activity directly and indirectly, through attractiveness. This theoretical model was tested using structural equation modeling on data from the largest repository of open source projects, Sourceforge.net.