Emma Johnston AO FTSE FRSN is the Dean of Science at the University of New South Wales and President of Science & Technology Australia. She is an authority in marine ecology and a former Pro Vice-Chancellor at UNSW.

Johnston's research group at UNSW investigates the ecology of human impacts in marine systems, combining the diverse disciplines of ecology, microbiology and ecotoxicology to expand fundamental understanding and provide recommendations for management. Her research is conducted in such diverse field environments as Sydney Harbour, Antarctica, the Great Barrier Reef and temperate Australian estuaries.

She is a regular media commentator and, as co-presenter of the Foxtel/BBC television series Coast Australia, which has helped take Australian marine science to an international audience. She also launched a Sydney Harbour cruise called Underwater Secrets' Sydney Harbour Revealed, which focuses on scientific research into the waterway.