Invested for the Future

Our commitment to building complementary platforms in construction, management, and engineering unlocks principled and meaningful growth. By focusing on the long-term and supporting our partner companies with capital and expertise they don’t just adapt – they thrive.

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FY20 Revenue​
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Top 400 ENR Contractors
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Employee Ownership
Partner Companies

Construction Services

Our construction services platform, STO Building Group, is a family of 12 companies with over 3,000 employees located in offices throughout the U.S., Canada, U.K. and Ireland.

Global Engineering & Consulting Services

Our parallel strategic priority is to complement the leadership position of STO Building Group’s Construction Management Services. Our Global Consulting Services platform brings together the complementary services and markets active in program and construction management, engineering consulting, and environmental services.

Select Projects from Our Partner Companies

Abbott Construction

Founded in 1983, Abbott Construction is a West Coast commercial builder known for superior planning and execution — serving a variety of sectors such as healthcare, hospitality, public works, education, non-profit, retail, tenant, and seismic improvements. Their expertise runs deep in pre-construction, project planning, and the timely and professional execution of the construction process.

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Ajax Building Corporation


Over the past 60 years, Ajax Building Corporation has established its presence throughout the United States and is now one of the Southeast region’s premier contractors. One of the fastest growing construction companies in the region, Ajax specializes in the educational, municipal, healthcare and cultural sectors. Whether the firm is renovating an existing facility or constructing a new complex, Ajax prides itself on delivering projects on time, within budget and with the highest level of safety, customer service and quality.

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Founded in 1986, BCCI Construction Company is a leading GC with offices in San Francisco and Mountain View, California. From new construction and major renovations to historic restoration and seismic upgrades, BCCI provides clients with a comprehensive construction experience from concept to completion.

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Govan Brown


Govan Brown is a full-service, Canadian construction management firm specializing in commercial interiors for the corporate, retail, and hospitality markets. Since 1994, the firm has completed thousands of projects for various clients from almost every industry. From boutique shops and vendor kiosks to multi-floor office fit-outs, their expertise and experience ensures each project is executed seamlessly and to highest standards.

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Layton Construction is a nationally-ranked commercial contractor with proven experience in virtually every industry, including healthcare, retail, hospitality, manufacturing, distribution, education, office, industrial, detention, tenant improvement, and public facilities. Headquartered in Utah, the 1,000-person firm also has offices in Arizona, California, Colorado, Florida, Hawaii, Idaho, and Tennessee. 

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LF Driscoll


Founded in 1929, LF Driscoll is the leading full-service construction provider in the Philadelphia metropolitan area. The firm specializes in the commercial, healthcare, cultural and higher education market sectors. Regarded as one of the nation’s leading healthcare facility builders, LF Driscoll offers the full range of construction management services to leading healthcare providers across the eastern and southwestern regions of the United States. With 90 years of construction expertise, LF Driscoll’s in-house capabilities guarantee each project’s quality, safety, schedule and budget.

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FLF Driscoll Healthcare combines LF Driscoll’s 90 years of experience building complex health systems with the Structure Tone organization’s breadth of local relationships and purchasing power. Together, these partnered firms offer unified teams of healthcare building experts to their clients across the nation.

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Founded in 1896, Pavarini North East Construction boasts a long history of providing the highest quality construction management and general contracting services to the northeastern United States. Today, 70% of the firm’s business stems from existing clients, which they support from offices in Stamford and Hartford, CT. From interior fit-outs and renovations to new building construction and infrastructure rehabilitations, Pavarini North East offers outstanding client services on every project.

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Pavarini McGovern


Pavarini McGovern provides construction management services for new buildings, major expansions and renewal projects in the New York metropolitan area. A firm made up of expert builders dedicated to the construction of enduring, high-quality buildings, Pavarini McGovern brings passion and creativity to each and every project. This approach allows them to deliver elegant solutions to complex construction challenges. As a result, PMG has built some of the finest and most imaginative structures in the area, earning their reputation for construction excellence.

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Structure Tone


Structure Tone was founded in New York City in 1971 as an interior and renovation construction company. Although the early 1970s were challenging economic times, Structure Tone flourished. Today, the firm is annually ranked as one of the top five contractors in New York City, and for nearly a decade, ranked as the #1 Interior Contractor by ENR. Structure Tone’s proven expertise managing construction in one of the world’s most challenging and dynamic regions is unmatched.

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Established in 1988, Structure Tone International is a leading construction service provider specializing in high quality fit-out, refurbishment and mission critical projects through offices in Ireland and the United Kingdom.

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