Following a long career in social housing, Jenny has embarked on research supported by the NHMF, to address the problem of inadequate ventilation in homes, which is damaging to both buildings and occupants' health. As homes become more airtight, ventilation strategy and performance assumes even greater importance. Ventilation systems are not ‘fit and forget’ arrangements - effective performance requires appropriate action by occupants and by maintenance. Jenny will share her findings and discuss how to promote good practice on ventilation in low energy homes. Follow up focus groups are being held throughout the day. What helps effective ventilation? What hinders?