  The spectrum of D2-branes wrapped on an ALE space of general ADE type is
determined, by representing them as boundary states of N=2 superconformal
minimal models. The stable quantum states have RR charges which precisely
represent the gauge fields of the corresponding Lie algebra. This provides a
simple and direct physical link between the ADE classification of N=2
superconformal field theories, and the corresponding root systems. An affine
extension of this structure is also considered, whose boundary states represent
the D2-branes plus additional D0-branes.
