  The purpose of this paper is to present the construction of a canonical
determinant functional on elliptic pseudodifferential operators associated to
the Guillemin-Wodzicki residue trace. The resulting functional is
multiplicative, a local invariant, and not defined by a regularization
procedure. The residue determinant is consequently a quite different object to
the zeta function (quasi-) determinant, which is non-local and
non-multiplicative.
