AAAI invites proposals for the 2013 Spring Symposium Series, to be held March 25–27, 2013 at Stanford University, Stanford, California. The Spring Symposium Series is an annual set of meetings run in parallel at a common site. It is designed to bring colleagues together in an intimate forum while at the same time providing a significant gathering point for the AI community. The two and one half day format of the series allows participants to devote considerably more time to feedback and discussion than typical one-day workshops. It is an ideal venue for bringing together new communities in emerging fields. The symposia are intended to encourage presentation of speculative work and work in progress, as well as completed work. Ample time should be scheduled for discussion. Novel programming, including the use of target problems, open-format panels, working groups, or break-out sessions, is encouraged. AAAI Technical Reports will be prepared, and distributed to the participants. Most participants of the symposia will be selected on the basis of statements of interest or abstracts submitted to the symposia chairs; some open registration will be allowed. All symposia are limited in size, and participants will be expected to attend a single symposium.