South Africa has the largest HIV treatment program in the world with over 4.5 million people on antiretroviral therapy. The country has made tremendous progress towards the UNAIDS 90-90-90 goals of getting 73% of those with HIV to be on treatment and to have an undetectable viral load, but monitoring progress towards that goal is hampered by the lack of a national monitoring database. In this talk, I will preview an approach to using probabilistic record linkage to turn a national laboratory database into a national HIV monitoring database, capable of describing trends in HIV care across South Africa. I will present preliminary results on the impact of various policy changes in South Africa and progress towards national and international targets.