The aim of the Journal is to provide a forum for the critical analysis of advanced drug and gene delivery systems and their applications in human and veterinary medicine. The Journal has a broad scope, covering the key issues for effective drug and gene delivery, from administration to site-specific delivery.In general, the Journal publishes review articles in a Theme Issue format. Each Theme Issue provides a comprehensive and critical examination of current and emerging research on the design and development of advanced drug and gene delivery systems and their application to experimental and clinical therapeutics. The goal is to illustrate the pivotal role of a multidisciplinary approach to modern drug delivery, encompassing the application of sound biological and physicochemical principles to the engineering of drug delivery systems to meet the therapeutic need at hand. Importantly the Editorial Team of ADDR asks that the authors effectively window the extensive volume of literature, pick the important contributions and explain their importance, produce a forward looking identification of the challenges facing the field and produce a Conclusions section with expert recommendations to address the issues.Articles review the current status of a specific topic, giving equal emphasis to the identification of major conceptual and technological challenges to successful drug and gene delivery, to an evaluation of triumphs as well as shortcomings in current conceptual and technical approaches, and to a discussion of their possible solution.