Titan Deng is an Attorney-in-Law and founded the law firm, Prisma Attorneys-at-Law, in 2016. The firm mainly provides legal services for LGBT+, sexual minority, HIV-positive, and substance-user clients. The areas of Deng’s practice include gender equality, same-sex marriage and family, equality claims and criminal defenses for persons living with HIV/AIDS, and substance addiction cases; he has also been the executive director or legal counsel for various organisations such as the Taiwan Tongzhi Hotline Association, Taiwan Equality Campaign, Taiwan Rainbow Civil Action Association (Taiwan Pride), and Persons with HIV/AIDS Rights Advocacy Association of Taiwan.