In this note, we briefly introduce singleton representations and discuss their relevance to the study of string and brane configurations in AdS space, their tensionless limit and the connection with higher-spin gauge theory. We then discuss the main properties of subcritical SO(D-1,2) WZW models featuring singletons and their composites as primary fields. After a suitable gauging, these models are good candidates for a fundamental, partonic description of tensionless branes in AdS. Their massless sector provides an affine Lie-algebraic setting for the study of higher-spin symmetries. Based on hep-th/0508124, hep-th/0701051 and work in progress.

7 pages, 1 figure. Contribution to the proceedings of the RTN project "Constituents, Fundamental Forces and Symmetries of the Universe" conference in Naples, October 9 - 13, 2006