Electrical, mechanical, and specialty contractors — plus the engineering/design firms behind them — executing the multi-year data-center build-out wave: high-voltage T&D infrastructure, power-line construction, and fiber deployment (Quanta, MasTec, Dycom, MYR Group, Primoris), full MEP commissioning and HVAC installation (EMCOR, Comfort Systems), data center campus site development and e-infrastructure earthworks (Sterling Infrastructure), fire protection, life safety, and specialty contracting for critical facilities (APi Group), and program/design engineering for hyperscale campuses and power infrastructure (AECOM, Jacobs, KBR).