Re: vulnerability criteria I would first talk to other organisations – criteria vary between countries and responses and are usually adapted to the local context and programming. It is also usual to try and be consistent between organisations to reduce conflict and issues at distribution and construction sites. There has been a lot of work in Sudan on this and I am sure that many organisations have developed criteria for their own distributions and programmes. In the absence of other shelter / NFI actors, WFP or their implementing partners are a good starting point. In addition to this, you can see examples of the kinds of criteria that are used in shelter programming in some of the case studies at http://www.sheltercasestudies.org. If you need further inputs, and are more specific about locations, we can have a look to see who we know who is working in the area, and who may be able to provide more specific support.