The topic of this review covers a very important branch of cancer research, cancer vaccination. The growing knowledge in tumor immunology has evolved rapidly, starting from nonspecific generic stimulation of the immune system to more specific approaches based on the availability of tumor antigens. The review covers molecular and cell biology, and pharmaceutical technology of cancer vaccines. Particularly, it is aimed at highlighting the results of cancer vaccines from phase II and III clinical trials, an issue that is of relevance to better understand how cancer vaccines can successfully complement antitumor therapy, including conventional chemotherapy and the recently developed target-based drugs.