Hatch Mott MacDonald (HMM) was a consulting engineering firm serving public and private clients in North America.

HMM's capabilities included planning, project development, studies and analysis, design, procurement, and construction engineering and inspection.

HMM originally provided the bulk of its services in transportation, including the design of tunnels, rail systems, bridges, highways, and airport infrastructure.

"[7] Highways and bridges, oil and gas pipelines, rail and transit, tunneling, and water and wastewater services are among the largest contributors to revenue.

From 2007 to 2012, HMM provided project management, preliminary design, environmental engineering, permitting, and right-of-way acquisition services for three segments of the California High-Speed Rail system, each with challenging elements.

These included to section between Palmdale, California and Los Angeles, which traverses rivers, mountains, densely populated cities, sensitive ecosystems, and three major fault lines.

At that point, DeNichilo became President and CEO of Mott MacDonald in North America following the separation of HMM into two distinct businesses.