This chapter discusses the available vector systems, particularly the recombinant adeno-associated virus (rAAV) vector, methods of gene delivery to the kidney, and the potential for gene therapy as a strategy for selected renal diseases. The strategies for gene delivery for application in renal diseases depend on the nature of the underlying disease as well as on the region of the kidney and cell types involved. The unique structure–function relationships and the multiple cell types present in the kidney are major barriers to the ultimate success of gene delivery to treat kidney diseases. The development of vectors to target specific cell types in the kidney and the design of regulatable expression systems would be of great interest. Among the available gene delivery systems, rAAV vectors have several distinct advantages. rAAV has a broad host range and is capable of transducing both dividing and non-dividing cells. rAAV results in long-term transgene expression, following a single application and infects cells with no significant side effects, particularly with respect to immune responses. © 2005, Elsevier Inc. All rights reserved.