In many contexts, Open Source (OS) is considered as an excellent opportunity on top of which it is easy to build new software systems. Moreover, it is common that companies use OS tools to create their commercial software, and even use OS COTS as parts of their products. However, in some cases, problems related to open source have been pointed out. Large software companies can face what they call "unfair competition" from communities. Furthermore, e.g. legal aspects of OS COTS can bear effect on what can be implemented and what not. In this talk, the focus is on balancing the different perspectives of OS software and its use in different contexts.