Since the first report in 2012 of a solid-state perovskite solar cell (PSC) with a power-conversion efficiency (PCE) of 9.7% and 500 h stability, research on perovskite photovoltaics has unprecedentedly and exponentially increased. Currently, certified PCE for perovskite solar cells tops 22.7%, which surpasses the PCEs of conventional thin-film solar cells. Perovskite solar cells are thus a disruptive technology in photovoltaics due to their low cost and superb performance. In this article, the emergence of PSCs is introduced, and an overview of progress in our laboratory is presented. In addition, future research directions that could lead to higher efficiencies are described. Beyond photovoltaic applications of halide perovskites, results for light-emitting diodes, resistive memories, and x-ray imaging are described.