Gillian is a professor of microbiology and with the Faculty of Science at the University of Auckland. She was formerly Associate Dean of Research and Head of the School of Biological Sciences. She is Chair on the Board of Grafton Halls of Residence and Deputy Director of the Centre for Microbial Innovation. Gillian is a former President of the New Zealand Microbiological Society. She has a PhD in Microbiology from the University of Otago. Her research focuses on the interactions of complex microbial communities and their response to natural and anthropogenic impacts in freshwater environments.