Based on experiences with the evolution of VO standards, this talk will suggest criteria when a standard ought to introduce MUST-type requirements on implementations and when it perhaps should not. I hope to show that there is a strong link between whether some constraint should be posed by a standard and whether that constraint can (and indeed must) be validated.
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Mark Taylor: "Validation for VO standard authors"
Every effort should be made to ensure that VO standards documents are correct and consistent with both themselves and with other VO standards. Failure to do that leads to confusion for implementers and users, and sometimes to the need for Errata at a later stage. Using validation tools during the document preparation process can help with this aim. This is a review of what items of content in VO standards documents can and should be validated during the document preparation process, and of tools and best practice that can be used.
Raffele D'Abrusco: "The Virtual Observatory at the Chandra X-Ray Center: past, current and future"
The Chandra X-ray Center (CXC) has a long history of direct involvement with the implementation and development of VO standards and protocols. In this talk, I will describe the array of IVOA interfaces currently maintained by the CXC and provide usage statistics. I will also mention future plans and some of the lessons learned along the way.