He held multiple administrative appointments at IMH over the years, including the Programme Director of National Addictions Management Service from 2017 to 2024; the Vice-Chairman Medical Board (Clinical) from 2012 to 2021; Head of the Emergency Services from 2015 to 2021; the Programme Director of Mobile Crisis Service from 2007 to 2021; the Chief of the Department of Community Psychiatry from 2004 to 2014 and the Programme Director of the Community Mental Health Team from 2007 to 2017.
Dr Lee is an Adjunct Associate Professor at Lee Kong Chian School of Medicine, Nanyang Technological University and an Adjunct Assistant Professor at Yong Loo Lin School of Medicine, National University of Singapore.
Dr Lee has been a fellow with the Academy of Medicine, Singapore (Psychiatry) since 2003. He is currently the Vice President of the College of Psychiatrists and was the former Chairman of the Section of Addiction Psychiatry.
Dr Lee is currently the President, Singapore Association for Mental Health.