The Human Proteome Project (HPP) of the Human Proteome Organization (HUPO) aims to find high-stringency evidence for all proteins encoded by the human genome, the major splice forms of each protein, mature N- and C-termini, and their major protein post-translational modifications (PTMs). Indeed, one cannot do the best biology and/or medical research without a complete understanding of the parts of the human proteome. Conversely, the international C-HPP teams need the input of biology/disease (B/D) teams to understand the biological context of the parts list. It is a question of focus. A focus on the parts list promotes a measurement- and detail-focused analytical mindset, while a focus on the biological context is focused on outcomes and may ignore individual parts in the context of the overall picture. In conclusion, both mindsets are indivisible parts of the larger HPP initiative.