  We construct two-dimensional N=(2,2) supersymmetric gauge theories with
orthogonal and symplectic groups using branes and orientifold planes in Type
IIA string theory. A number of puzzles regarding the construction, including
the effect of exchanging NS5-branes on an orientifold 2-plane, are resolved by
lifting the configurations to M theory. The low energy properties and
conjectured dualities of these theories are reproduced in the M-brane
description. A similar construction of N=(4,4) theories with orthogonal and
symplectic groups leads to new duality conjectures for these theories.
