Innovation in the therapeutics of intestinal disorders depends critically on the delivery of drugs into the appropriate region of the intestinal tract, where to overcome the harsh acid environment of stomach. The work of this innovative and challenging book is that to development of hard gelatin capsule has been restricted within the said region. The author/s, a well researchers in the study of the Gastro intestinal drug delivery systems and its implications associated with the drug release. An existing materials for drug delivery and targeting are reviewed and a representative range of excipients and delivery systems is considered in studies. Particular attention has been paid to the hard gelatin shell, and its cross linking with the different aldehyde derivatives. Although a single book and its research can never cover all aspects of so broad a topic, the editors hope that this book will serve as a useful introduction to pharmaceutical researchers, especially those who are new to this field of research, and a valuable addition to those who are already familiar with this subject.