This book belongs in both graduate and undergraduate libraries as a useful reference for students and researchers in topology. It is directed toward mathematicians interested in geometry who have had at least a beginning course in topology. It should provide the reader with a better understanding of the physical properties of Euclidean 3-space--the space in which we presume we live. The reader should learn of some unsolved problems that continue to baffle reseachers. The most profound result in the volume is the side approximation theorem. However, some of the preliminary results and some of the applications may be used more frequently for reference.