The impact of ventilation on energy use can be considerable. Total building energy use is variously estimated to account for 30% of all energy consumed in International Energy Agency countries. Of this, as much as 50% can be associated with ventilation and air infiltration. As living standards throughout the world improve, it may be expected that building occupants will demand ever-increasing standards of comfort. This will inevitably result in increased demand on building energy use and further heighten concerns over global pollution. Much can be achieved to reduce energy demand by improving energy efficiency. However, as the thermal performance of buildings improves, ventilation will become the dominant source of building energy loss. Unfortunately, reducing ventilation as a means to minimise energy demand, has become inextricably linked to problems associated with unhealthy buildings. Ventilation is thus an essential parameter in both energy and indoor air quality control. The purpose of this report is to assess future ventilation research and development needs. An objective has been to identify the prime objectives and tasks needed to secure energy efficient ventilation without detriment to indoor air quality.