A discussion of many of the key design issues for building search engines. It emphasizes the important roles that applied mathematics can play in improving information retrieval. The authors discuss not only important data structures, algorithms and software, but also user-centred issues such as interfaces, manual indexing, and document preparation. The authors bridge the gap between applied mathematics and information retrieval. They discuss some of the current problems in information retrieval that may not be familiar to applied mathematicians and computer scientists and present some of the driving computational methods (SVD, SDD) for automated conceptual indexing. This book introduces topics in a non-technical way and provides insights into common problems found in information retrieval. The more mathematical details are provided in sidebars or offset from the regular text.