The adeno-associated virus (AAV) is one of the most promising viral vectors for human gene therapy. As with any potential therapeutic system, a thorough understanding of it at the in vitro and in vivo levels is required. Over the years, numerous methods have been developed to better characterize AAV vectors. These methods have paved the way to a better understanding of the vector and, ultimately, its use in clinical applications. This review provides an up-to-date, detailed description of essential methods such as production, purification and titering and their application to characterize current AAV vectors for preclinical and clinical use.