In a career spanning 35 years, she served as a Senior Lecturer in the Faculty of Law of the University of Colombo for 17 years and as Deputy Chairperson and member of the National Child Protection Authority.
As a trustee of the Vishva Niketan International Peace and Meditation Centre in Sri Lanka (the spiritual arm of Sarvodaya), she co-founded the psycho-spiritual healing programme for Sri Lankan prison inmates, in 1999, the 3S Spiritual Retreat entitled ‘Searching the Self, Serving Society and Saving the Environment’ for Stress Reduction in 2017 and ‘Sahana Mithuro’ Programme in 2019 to provide psycho social and psycho spiritual support services to survivors of natural and manmade disasters. She has been a mindfulness trainer and a practitioner for the past 15 years. In March 2021 Dr. Marasinghe completed a one-year long teacher training on Mindfulness based Cognitive Therapy (MBCT) at Oxford Mindfulness Centre, University of Oxford.