The aim of this book is to provide both a rigorous view and a more practical, understandable view of nanosystems for graduate students and scientists in related fields. This book wants to satisfy readers with both direct and lateral interest in the discipline. This volume is structured into different parts devoted to nanotechnology and drug delivery systems and their applications. Every section of the book has been expanded where relevant, to take into account significant new discoveries and realizations of the importance of key concepts. Furthermore, emphasis is placed on the underlying fundamentals and on acquisition of a broad and comprehensive grasp of the field as a whole.