Further details can be found on the ALSPAC website: http://www.bristol.ac.uk/alspac/, including the full ALSPAC collaboration policy (http://www.bristol.ac.uk/alspac/documents/alspac-policy.pdf). This resource also details all ALSPAC data (on mothers, index children and other relatives) that are currently available to external collaborators. At the present time, the ALSPAC resource is set up as a supported access resource rather than as an open access resource. In brief, any researcher wanting to use ALSPAC data must complete an ALSPAC Research Proposal Form describing the proposed collaboration and send it to the ALSPAC Executive (alspac-exec@bris.ac.uk). The ALSPAC executive will reply, usually within 2 weeks, to inform the applicant of the outcome and provide advice on the next stages. The vast majority of requests are approved as the system only checks availability of data and whether a cost will need to be charged (in most cases <£1000) to cover the staff resources required to put together a data set for collaborators. We do not police overlaps between requests, but since July 2011 all approved projects are detailed on the website (address as above), so potential collaborators can see
