Inverse boundary problems are a rapidly developing area of applied mat hematics, and inverse boundary spectral problems (IBSP) constitute an important and distinct part of the field because of the special charac ter of the data involved, the specific methods used to deal with that data, and their relevance to applications, including medical imaging and geophysical prospecting. Although the theory of IBSP has been in d evelopment for at least 10 years, until now the literature has been sc attered throughout various journals. This self-contained monograph sum marizes IBSP concepts and the...