While there is firm astrophysical evidence for dark matter, fundamental properties of the substance, such as its constituent size and mass, remain key open questions in modern physics. The xenon Time Projection Chamber (TPC) technology leads searches worldwide for particle dark matter with masses around the proton mass and above. The LUX-ZEPLIN (LZ) dark matter search features a 10 tonne xenon TPC that is currently in its commissioning phase. Over its 5 years of operation, LZ expects to improve upon the current dark matter sensitivity by a factor 30 beyond the current best results. In this talk, I will illustrate the powerful features of LZ that enable us to achieve such sensitivity, as well present R&D activities of the SLAC LZ group, including those aimed at upgrades for LZ and the next generation of dark matter searches.