After the loss of ASTRO-H, JAXA conducted a thorough mishap investigation, and derived an extensive list of lessons learned. These lessons are being rigorously employed in the development of the new X-Ray Imaging and Spectroscopy Mission (XRISM). Building on the successes of the ASTRO-H mission, XRISM will perform the high-resolution X-ray spectroscopic observations of the hot gas plasma wind that blows through the galaxies in the universe. These observations will enable us to determine flows of mass and energy, revealing the composition and evolution of celestial objects. This innovative, JAXA-led international project will be developed in collaboration with NASA, ESA, and other highly-qualified partners. XRISM will carry forward the ambitions and successes of ASTRO-H, and will deliver the highly-anticipated scientific results to the world.