Abstract: The Habitable Worlds Observatory (HWO), NASA’s next generation flagship observatory, will revolutionize multiple areas of astrophysics and provide nearly flyby-quality observations of a panoply of solar system targets. While the atmospheres of rocky, temperate planets around M dwarfs are accessible to JWST, a next frontier of astronomy and planetary science is to directly image temperate Earth-sized in planets in the habitable zones (HZ) of Sun-like stars, measure their spectra, and search for signs of life. HWO will directly image ~25 rocky HZ planets around Sun-like stars, providing the first ever constraints on the occurrence of habitability and life on planets with star-planet evolutionary histories analogous to Earth’s, and possibly best the opportunity to detect unambiguous biosignatures. The gases in the spectra of these precious targets will be considered in the full context of their planetary and stellar environments to rule out biosignature false positives. To broaden our understanding of what a habitable and inhabited world may look like, the HWO team will consider the diverse environments and dominant biospheres of Earth’s long geological history to guide the search strategy, as well as biospheres different from Earth’s history. This presentation will provide an overview of current thinking on HWO strategies for the search for life outside the solar system. The survey of the atmospheric compositions of dozens of potentially habitable worlds will be one of the most challenging goals of any NASA observatory ever flown, will bring about a revolution in our understanding of planetary formation and evolution, and may usher in a new era of comparative astrobiology.