Author: Philip Osterlund Institution: University of Minnesota Abstract: This thesis is aimed towards the determination of tensor decompositions of the regular representation of finite p-groups over fields of characteristic p. We also focus on uniserial modules, as they are often factors. We develop an algorithm that determines, up to isomorphism, all uniserial modules of a group ring (Section 2, pp. 11-12). In a tensor decomposition of the regular representation of a group, we relate the Loewy lengths, radical series and socle series of the regular representation to those of the factors (Theorems 1.4-1.7, pp. 69-74). Under certain conditions, we find that the Poincare polynomial associated to the filtration of a module is the product of the corresponding Poincare polynomials of the module's tensor factors (Corollary 1.8, p.73). For the non-abelian groups of order 16 that can not be written as direct products of proper subgroups we classify the uniserial modules (Chapter 2, pp. 23-66) and all tensor decompositions (Section 3, pp. 85-111). Status of paper: This is a University of Minnesota thesis which was accepted for the degree of Ph.D. in 1997. The subject matter of the thesis has not yet appeared elsewhere.