True, precise and complete documentation of artefacts is essential for conservation and preservation of our cultural heritage (CH). Through access to the knowledge about best possible documentation of artefacts it's possible to support an enhanced understanding of material CH and its long-term preservation. Documentation of CH involves researchers, scientists and professionals from multiple disciplines and industries. All of them are contributing in different ways to a documentation process, have different background and correspondingly different views on this process. In order to end up with best possible digital representations supporting subsequent research questions and applications in an optimal way it's important to build a common base linking technical views with those from CH experts. COSCH aims to help building this common understanding through close cooperation on a concerted European level as typically provided through COST Actions. COSCH will address some key interdisciplinary questions concerning the development of optical measuring techniques and electronic imaging applied to documentation and presentation of artefacts, as identified through the work of Colour and Space in Cultural Heritage (www.COSCH.info). More than 200 international researchers and professionals participate in COSCH activities which have been organised around six main subjects: (1) spectral object documentation, (2) spatial object documentation (3) algorithms and procedures (4) analysis and restoration of cultural heritage surfaces and objects, (5) visualisation of cultural heritage objects and its dissemination, (6) the semantic development of the COSCH Knowledge model. The latter one tries to provide the collected mutual knowledge in a structured way to the scientific community allowing to get necessary recommendations in order to select a most appropriate documentation process