This book is the first of its kind to provide a large collection of bioinformatics problems with accompanying solutions. In particular, a number of problems covering all the problems offered in Biological sequence analysis (BSA), et al Durbin, widely adopted as a required text for bioinformatics courses at leading universities around the world .. Although many of the problems included in BSA as exercises for the reader who has been repeatedly used for homework and tests, no detailed solutions to problems that are available. Bioinformatics instructors had therefore frequently expressed a need for fully worked solutions and a set of larger problems to be used in the program. This book provides just that: following the same structure as BSA and significantly expand the set of problems can be applied it will facilitate a better understanding of the contents of the chapters in BSA and will help the reader to develop problem solving skills are very important for success developing research in the field of bioinformatics. MARK BORODOVSKY is Professor of Regents' Biology and Biomedical Engineering and Director of the Center for Bioinformatics and Computational Biology at the Georgia Institute of Technology in Atlanta.