The goal of this project was to recommend empirically based strategies to prevent building-related symptoms in office buildings, for owners and managers. Ideas from six experienced building investigators were gathered and prioritized in a multi-day workshop. The top ranked problems identified were, in priority order: excessive building moisture, inadequate outdoor air, excessive dust, pollutant gases and odors, inadequate thermal control, and inadequate attention by management to indoor environments. Available findings in the scientific literature were generally consistent with these recommendations. The highest priority strategies recommended for preventing buildingrelated symptoms were: managing water at building exteriors, operating ventilation systems per design intent, providing at least minimum ventilation rates, and maintaining indoor temperatures at 22°C ± 1° (72°F ± 2°). Despite the range of climates in which they worked, IEQ investigators showed considerable agreement, including top-ranking managing of water at building exteriors as a prevention strategy. Effi- cacy of these empirically based strategies generally has not been confirmed.