Nanowire lasers are miniaturized light sources with great potential for integration into optoelectronic circuits. Many of the current nanowire lasers either require extreme conditions for synthesis or suffer from poor operational stability. We synthesize nanowires of a promising set of compositions, the cesium lead halides, and accomplish this under near-ambient conditions. These nanowires act as efficient laser cavities and are capable of lasing with relatively low excitation thresholds. They also demonstrate unprecedented stability for a perovskite-based nanowire laser and offer a new nanoscale platform for future study.