IntroductionL e t R be a commutative ring with 1. If I is a finitely generated (f.g.) ideal in R, then I is a projective ideal iff I is a multiplication ideal and ann (I) is generated b y an idempotent [9]. The main goal of this paper is to s t u d y the relationship between f.g. projective modules and multiplication modules.Recall t h a t a right module P is said to be a multiplication module if every submodule N of P has the form P I for some ideal I of R [1]. On the other hand, a f.g. projective module P is called hereditarily projective if every homomorphic image of P into a f.g. projective module is projective. Equivalently, if l(P) is a projective ideal of R for each linear functional I on P (i.e. l E P*, the dual of P). The projective module P is called cohereditarily projective if the closure of each f.g. submodule N of P is a direct s u m m a n d in P [2].The main result of this paper is that for indecomposable f.g. modules P over P.P. rings R, P is hereditarily projective iff P is a multiplication module and ann (P) is generated b y an idempotent (see Theorem 2.7).I t was proved in [2] t h a t a f.g. module P is hereditarily projective iff P* is cohereditarily projective. I t is proved in this paper t h a t these two concepts are equivalent if P is indecomposable and R is a P.P. ring (see Theorem 2.8).Finally, we remark t h a t all rings in this paper are commutative with 1, and all modules are unitary. For basic ideas on multiplication ideals see [4]. §-1. Preliminaries