Canonical induction formulae and the defect of a character Robert Boltje University of California, Santa Cruz Abstract: We explain the idea and the machinery of canonical induction formulae with going as little into details as possible and show that a certain version keeps track of the $l$-defect $d(\chi)$ of an irreducible character $\chi$ of a finite group $G$ by mapping $\chi$ precisely to the $d(\chi)$-th layer in the filtration $A\subseteq l^{-1}A\subseteq l^{-2}A\ldots$, for a prime $l$ and a certain free abelian group $A$. Published in: Representation theory of finite groups; Proceedings of a special research quarter at the Ohio State University, Spring 1995, R. Solomon (ed.), De Gruyter, Berlin 1997, 29-44.