The annual world congress of Human Proteome Organisation (HUPO) is one of the premier meetings in proteomics. Rotating between Europe, North America and Asia/Oceana, this year's host city was Amsterdam, The Netherlands. Proteomics still being a rapidly evolving field, HUPO meetings provide a platform for technical advancements in protein purification and separation techniques, innovations in mass spectrometry and applications in bioinformatics and computational biology. A special focus of this year's meeting was on proteome biology, indicating that the state of technology has progressed to a level permitting interrogation of biological systems in a meaningful way.