Transdermal drug delivery system has become the focus of formulation research in the last decade owing to its advantages like easy accessibility, non invasiveness, compliance, safety and effectiveness. In United States around 40% of the drug delivery candidate products under clinical evaluation were related to transdermal or dermal systems. Nevertheless, its clinical application has been limited due to barrier properties of skin, especially the stratum corneum. To enhance the permeation of drugs through the skin many attempts have been made by the investigators that led to development of several technologies. The prodrug approach represents an alternative and promising method of enhancing the skin permeability of drugs by increasing the lipophilicity. Iontophoresis technique has been gaining much popularity by overcoming skin barrier to drugs and by expanding the range of drugs that could be administered through the transdermal route. This book describes about the synthesis of prodrugs of selected antihypertensive agents, assessment of physicochemical properties and in vitro assessment by passive permeation and iontophoresis for transdermal delivery.