Europeana has partnered in many projects where annotations play a big role, either as a part of a general crowdsourcing approach or more specialized ‘nichesourcing’ scenarios. The motivations and concrete goals of these projects are diverse, but some commonalities can be found in terms of the requirements for motivation and provenance. These requirements are very simple, but in a very fragmented domain, even the obvious needs to be stated and agreed on. Best practices should be encouraged, especially for exchange of data and interoperability of tools and services built on top of them. In this respect, the Open Annotation initiative is crucial, and the Europeana R&D team has been following and contributing to their work for several years already. In our presentation we will present what our different projects are (DM2E, SEALINCmedia, EuropeanaSounds, W3C Data on the Web Best Practices), together with examples of annotations made, hoping this will help the workshop identify common denominators for the various approaches to annotation in the research community and beyond.