DNA delivery into cells is a rapidly developing area in gene therapy and biotechnology. Moreover, it is a powerful research tool to determine gene structure, regulation, and function. Viral methods of DNA delivery are well-characterized and efficient, but little is known about the toxicity and immunogenecity of viral vectors. As a result, non-viral, transfection methods of DNA delivery are of increasing interest. Synthetic DNA Delivery Systems is a comprehensive and current resource on DNA transfection. The use of histidine-rich peptides and polypeptides as DNA delivery systems and self-assembled delivery systems based on cationic lipids and polymers are discussed. Targeted delivery to organelles, tumor cells and dendritic cells comprise an important topic.