  We present an introduction to boundary value problems for Dirac-type
operators on complete Riemannian manifolds with compact boundary. We introduce
a very general class of boundary conditions which contains local elliptic
boundary conditions in the sense of Lopatinskij and Shapiro as well as the
Atiyah-Patodi-Singer boundary conditions. We discuss boundary regularity of
solutions and also spectral and index theory. The emphasis is on providing the
reader with a working knowledge.
