The second Human Brain Proteome Project (HBPP) Workshop of the Human Proteome Organisation (HUPO) took place at the Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI) from April 23-24, 2004. During two days, more than 70 attendees from Europe, Asia and the US came together to decide basic strategic approaches, standards and the beginning of a pilot phase prior to further studies of the human brain proteome. The international consortium presented the technological and scientific portfolio and scheduled the time table for the next year.