Associate Professor Brett Toelle is the Deputy Director of the Woolcock Institute of Medical Research. He is also a Principal Research Fellow working within the Respiratory and Environmental Epidemiology Group. For over 30 years he has been involved in the population studies of lung disease which have included studies of pre-school children, schoolchildren, twins, community based adults and occupational work groups. His recent work has focussed on asthma as the participants in the Childhood Asthma Prevention Study (CAPS) transition through puberty and on COPD as part of the Australian Burden of Lung Disease (BOLD) project of adults aged 40+ years from six sites around the country.

He is also a psychologist and undertook a PhD investigating "Factors associated with non-adherence to prescribed asthma medication". During his psychology internship he worked with psychologists in the sleep research group and clinicians at the Royal Prince Alfred Insomnia Clinic.