  In the noncommutative field theory of open strings in a B-field, D-branes
arise as solitons described as projection operators or partial isometries in a
$C^*$ algebra. We discuss how D-branes on orbifolds fit naturally into this
algebraic framework, through the examples of $R^n/G$, $T^n=R^n/Z^n$, and
$T^n/G$. We also propose a framework for formulating D-branes on asymmetric
orbifolds.
