We at VisionMobile have been researching, investigating and helping to educate the industry about open source for the past five years. In this time open source software has been transformed from geekware to business as usual. Much has been written and debated regarding open source licenses - from the early days of the GPL license to the modern days of the Android platform.Despite the widespread use of open source, from Android to WebKit, there is one very important aspect that has been neglected: openness and how to measure it.