Design theory is a branch of combinatorics with applications in number theory, coding theory and geometry. In this book the authors discuss the generalization of results and applications to quasi-symmetric designs. The coverage is comprehensive and will be useful for researchers and graduate students. An attractive feature is the discussion of unsolved problems.

"...researchers in design theory should find this monograph to be a valuable resource." A.R. Calderbank, Bulletin of the American Mathematical Society

"The authors have done a thorough job of surveying the literature up to the time they wrote the book." Sylvia A. Hobart, Mathematical Reviews