S-THEORY

The representation theory of the maximally extended superalgebra with 32 fermionic and 528 bosonic generators is developed in order to inves tigate nonperturbative properties of the democratic secret theory behi nd strings and other p-branes. The presence of Lorentz nonsinglet cent ral extensions is emphasized, their role for understanding up to 13 hi dden dimensions add their physical interpretation as boundaries of p-b ranes are elucidated. The criteria for a new larger set of BPS-like no nperturbative states is given and the methods of investigation are ill ustrated with several explicit examples.