Willdan Group, Inc. traces its roots back to 1964 when two engineers, William Stookey and Dan Heil, founded a small contract engineering and planning business in California to help local governments manage growth and infrastructure. Initially serving municipalities with civil, building, and planning services, the company gradually expanded both in scale and technical breadth. Over the years, it has grown by adding specialized practices, spinning out energy and software capabilities, and acquiring firms that broaden its service portfolio.
Today, Willdan operates through two principal segments (as commonly described): Energy and Engineering & Consulting. The Energy segment delivers energy efficiency, sustainability consulting, program management, energy engineering, and software analytics for utilities, governmental agencies, and commercial or institutional clients. The Engineering & Consulting segment provides municipal and civil engineering services: city planning, public works design, building & safety oversight, geotechnical and material testing, construction management, and related disciplines.
In its operations, Willdan maintains a broad geographic footprint, with offices in many U.S. states and a presence in Canada. It has built long-standing relationships with municipal governments, public agencies, investor-owned and municipal utilities, and private industrial / commercial clients. The company frequently serves as an outsourced technical partner—extending the capacities of public agencies and utilities by supplying in-house engineering, energy program execution, software tools, and consulting support. With more than 1,700 employees delivering contract revenue in the hundreds of millions, it delivers integrated solutions across energy, grid modernization, municipal infrastructure, and planning.
Positioned at the intersection of infrastructure, energy transition, and public agency consulting, Willdan aims to be a key enabler of clean, resilient, and efficient communities. Its strengths include its embedded municipal relationships (some going decades), diversified service offerings (from energy analytics to civil engineering), and ability to combine consulting, software, and technical execution. As energy and infrastructure needs evolve (electric grid modernization, decarbonization, resilience), Willdan’s model as a technical partner to agencies, utilities, and developers gives it levers for growth across multiple domains.