Cassey started at The South African Depression and Anxiety Group (SADAG) as a volunteer counsellor in the call center helping to man the Suicide Crisis Helpline over 12 years ago. With a background in Psychology, and experience as a volunteer in the call center she then took on the position of Call Center Manager managing over 100 volunteer counsellors. After 10 years with the organization, she is now the Operations Director and  a board member. She represents SADAG at national conferences, various press interviews, workshops and advocacy projects to help fight for patients’ rights and destigmatize mental health across the country. She focuses on various projects including the Teen Suicide Prevention school programme, rural outreach projects, support groups, responsible reporting initiatives with press and media, mental health in the workplace and more recent advocacy projects including the Esidimeni crisis and medical aids such as the Health Market Inquiry.