Alan Osborne Trounson AO (born 16 February 1946) is an Australian embryologist with expertise in stem cell research. Trounson was the President of the California Institute for Regenerative Medicine between 2007 and 2014, a former Professor of Stem Cell Sciences and the Director of the Monash Immunology and Stem Cell Laboratories at Monash University, and retains the title of Emeritus Professor. Trounson's areas of interest include cloning, stem cells, biotechnology, cloning for agricultural industry, gene storage and in-vitro fertilisation.