High-Energy Lasers (HELs) are emerging as a transformative element of layered defense, offering speed-of-light engagement, scalable effects, deep magazines, and low cost per shot. This white paper outlines HEL fundamentals, operational advantages, acquisition pathways, and technical challenges with mitigations. It highlights HII Mission Technologies’ role in accelerating HEL adoption through systems integration, mission engineering, and sustainment—providing a strategic roadmap to operationalize directed energy across domains.