  If G is a pro-p, p-adic, Lie group and if $\Lambda(G)$ denotes the Iwasawa
algebra of G then we present a formula for determining the $\Lambda(G)$-rank of
a finitely generated $\Lambda(G)$-module. This is given in terms of the G
homology groups of the module. We explore some consequences of this for the
structure of $\Lambda(G)$-modules.
