You may already have had a chance to look through the recent offering from DPE - the PLATTER tool. If you haven't already done so, then it's well worth a look. At fifty-odd pages long you'll need a bit more than five minutes, but it's a really interesting proposal for approaching planning for a new repository.
PLATTER stands for the Planning Tool for Trusted Electronic Repositories. The approach defines a series of nine Strategic Objective Plans that address areas considered by the DPE team as essential to the process of establishing trust. Each plan is accompanied by a series of key objectives and goals. Achieving these goals enables a repository to meet the 'ten core principles of trust' defined by the DCC/DPE/NESTOR/CRL early in 2007. Working these goals into the planning stage of the repository - and of course achieving them - should therefore put the repository in a good position to be recognised as a trusted Digital Repository at a later date. This is of course dependent on carrying out a TDR audit such as DRAMBORA, NESTOR or TRAC.
PLATTER is a really comprehensive and well thought-out checklist which has been designed to be flexible enough for use with a range of different types of repository, from IRs to national archives. So whilst it may look a bit daunting at first, it should be adaptable enough that different institutions - which may perceive themselves to have different approaches and requirements for trustworthiness - can use it. However, given that many smaller repositories (particularly IRs) have already decided that preservation - and by implicit association, trust - is something that can be put to one side and addressed at a later date, I find myself wondering just how many of them will actually use this tool when still at the planning stage.