Abstract: While there is tremendous astrophysical and cosmological evidence for dark matter, its precise nature is one of the biggest open questions in modern physics. The DarkSide experiment is looking for WIMP dark matter using a liquid argon target located deep underground at Gran Sasso National Laboratory (LNGS) in Italy. DarkSide-50 is the first physics-capable detector in the DarkSide program, currently filled with argon obtained from underground sources, which is greatly reduced in radioactive 39Ar. DarkSide-50 recently made the most sensitive measurement of the 39Ar activity in underground argon and used it to set the strongest WIMP dark matter limit using liquid argon to date. Overviews of the DarkSide program and of the recent results from DarkSide-50 will be presented. R&D activities at UCLA related to the liquid argon technology for dark matter searches will also be presented.