Most of the 29 papers report original research, but some review literature in the field. The topics include linear source modules and trivial source modules, homomorphisms in higher complexity quotient categories, the infinite order of the symplectic classes in the cohomology of the stable mapping class group, the category of Mackey functions for a compact lie group, the relation between simple groups and homotopy theory, applications of stable classifying space theory to group cohomology, the code of a regular generalized quadrangle of even order, and quivers of blocks with normal defect group. Also poses 41 open questions. Addressed to graduate and research mathematicians and physicists. No index. Annotation copyrighted by Book News, Inc., Portland, OR