"A piece of content or data is open if anyone is free to use,  reuse, and redistribute it — subject only, at most, to the requirement  toattribute and share-alike ( http://opendefinition.org/ ). Driven by demands on government, freedom on information and an increased perception of their value, open data have seen dramatic growth in the past two years: is archaeology part of this general trend? Are we ready to embrace open data on a non-episodic basis? The aim of the working group on open data in archaeology is to explore what does it mean to make archaeological data open and what processes are required to make it happen. There are three major goals: 1. Individual and institutional advocacy 2. Ethical discussion and consensus-building (e.g. a basic agreement on the above open definition) 3. Knowledge transfer (licenses guidance, wider academic context, repositories etc.)
The link between funding, publication and open data is a key area for advocacy of open data. So, the need to encourage national funding agencies, and international ones (private or public) to build in open data policies into the requirements of their grants and to check for such a track record in subsequent grants. On the other hand, there is a need to make open data a more relevant part of the publication and research process, and not just an afterthought. At the level of individual advocacy, producing open data can increase the value and impact of one's work (just like open access). Is this a different agenda to the one espoused for 'interoperabilty' (linguistic, technical, etc.)? Yes, it questions/reopens debate about whether rich semantics and structured ontologies are really more important than liberal licensing and access. Is quick and dirty, but open more important? Are the two in step with each other or potentially at odds?

2. Ethical discussion
Discussion on ethics and formulation of ethical guidelines are necessary to deal with ethical dilemmas about e.g. sharing data across sovereign borders, or the existence of justifiable delay in making data open (e.g. a grace period to allow for individual use). With specialisation in terms of geographic regions, time periods, kinds of archaeological expertise -- has also come balkanisation. There are very few attempts to synthesise at a large scale, and typically in the rare cases that this occurs, it is on the part of one-off mega-projects whose data also remains closed. Open data provides a
pathway for us to return to the kinds of synthetic perspectives last possible many decades ago. 

3. Knowledge transfer
The working group encourages researchers to actively avoid producing and using closed data wherever possible. (e.g. not  mixing closed data with open data in analyses wherever this is avoidable). Wiki-style advice and best practices for those who choose to "go open" are among the intended deliverables.