Since publication of the first edition of this Handbook, the usage of thenno­ plastic elastomers (TPEs) has doubled, with a compounded annual growth rate of approximately 9 percent. This second edition summarizes and documents the technological and commercial progress that has given rise to this phenomenal rate of growth. Over the past decade, numerous suppliers and users of ther­ moplastic elastomers have entered the field, and some have retired from it, a process that almost certainly will continue. This Handbook is intended to serve the broad spectrum of professionals ac­ tively engaged in the field of thennoplastic elastomers, which has seen a growth rate four to six times that of the rubber and plastics industries. As TPEs embrace both rubber and plastics technology, this book will be useful to rubber and plastics technologists with a broad variety of specific interests. This edition emphasizes commercial practice and practical application rather than research activity. Technology and innovation are stressed, with polymer science functioning as a basis for understanding and communication. We have focused on those TPEs that we consider to be of significant commercial impor­ tance-the ones now used in the fabrication of useful articles, or which probably will be so used in the foreseeable future.