This presentation will review the results of recent research at the Bartlett, including the following:1. The limitations of the Olf and Decipol.2. CO levels in UK houses and the impact of ventilation strategies3. Health and comfort in air-conditioned offices compared to naturally ventilated.4. The use of passive design features such as atria and blinds in buildings5. The new variable artificial sky with integral sun at the Bartlett.6. CANDLE: A Lighting designers' interface to RADIANCE.7. Pollutant concentrations and RH stability in air-conditioned and naturally ventilated museums in the UK.8. Lessons learnt from providing energy design advice to over 1000 building projects.