As open source development's acceptance has increased, many companies have incorporated it into heterogeneous development, which creates products by combining software that's from many sources and built with many different processes. To be effective, heterogeneous development must bridge the gap between industrial and open source software (OSS) development practices. One aspect of this approach is inner-source development, which aims to deploy key aspects of OSS development within a limited scope - for example, a division, a company, or even a consortium. So, industrial software development must be extended with knowledge of how to cooperate in open source and inner-source communities. To compete successfully, software-intensive companies will need to adopt new forms of collaborative development involving open source software.