Capraro, MaximilianRiehle, DirkBecker, SteffenBogicevic, IvanHerzwurm, GeorgWagner, Stefan2019-03-142019-03-142019978-3-88579-686-2https://dl.gi.de/handle/20.500.12116/20876Inner source (IS) is the use of open source software development practices within an organization. The organization still develops proprietary software but internally opens up its development. The research area lacks a systematic assessment of known research work: No model exists that defines IS thoroughly. Various case studies provide insights into IS programs in a specific context but only few publications apply a broader perspective. To resolve this, we performed an extensive literature survey and analyzed 43 IS related publications. Using qualitative data analysis methods, we developed a model of elements that constitute IS. We present a classification framework for IS and apply it to lay out a map of known IS endeavors. Further, we present qualitative models summarizing the benefits and challenges of IS. This article is an extended abstract of [CR17].eninner sourcetaxonomyopen collaborationinternal open sourcesoftware development methodssoftware engineeringsoftware development efficiencysoftware development productivityText/Conference Paper10.18420/se2019-181617-5468