The development of an effective vaccine is the only affordable and sustainable way to halt the HIV pandemic. In response to this challenge, the HIVACAT program was launched to design, develop and test potential HIV vaccine candidates in clinical trials for further development and regulatory approval. HIVACAT is a joint effort of two leading European HIV research institutions in Barcelona – The Hospital Clinic and Irsicaixa, and the pharmaceutical company, Esteve. This consortium also has the support of the Obra Social “La Caixa” Foundation (“Fundació la Caixa”) and two organizations of the government of the Generalitat de Catalunya (the Department of Health and the Department of Innovation, Universities and Companies). HIVACAT brings together the expertise and projects of more than 60 investigators from The Hospital Clinic and Irsicaixa, in addition to multiple international collaborations with leading HIV research organizations and institutions in Europe, Asia, Africa, Oceania and the Americas. Esteve's involvement consists in providing expertise in intellectual property, regulatory affairs, GMP production, GLP regulatory studies, and other aspects of preclinical and clinical development, in addition to providing funding.