I can take that one.
I think one of the ways to be successful in doing this is to first of all recognize that it's not easy. Open government requires a balance. There is a balance of competing interests.
It's natural for agencies to sometimes feel reluctant or to say their types of records are different, what they do is different, and there can't be openness on what they do because it's so sensitive. You have to walk people through what can be an initial resistance. They need to recognize that even though there's sensitive information that is properly protected and will be protected, everyone has room within their record systems and within the things they do. Everyone has room to be more open. Everyone can make a little progress.
Once you get it started, it helps to be able to point to another agency and say the CIA has actually managed to declassify and post some really interesting things. If the CIA can do it, they can do it too.