How we ranked
The ranking applies four criteria in priority order. Each firm was scored against the same four, and a firm that could not show the first one did not make the page.
The four ranking criteria
1. Verified closed deals in the sector, with public sources. A named engineering, architecture, environmental or infrastructure consulting sale on the firm's own site or in a dated press release. A deal count with no names counts for less than named deals.
2. A sector-dedicated team. A team or firm that works in architecture, engineering and environmental firms, rather than a generalist desk that happened to close one engineering deal.
3. Size band fit. A published revenue or enterprise value band that matches an owner-run firm, or deals of a scale a founder-led firm can use as a reference.
4. Founder-led engagement. Named partners or principals who lead the work, instead of hand-offs to junior staff.
Order inside the list follows criterion 1 first, then 2, then 3 and 4. That is why the five advisors with the longest public AEC deal lists sit ahead of Kinected, and why the large banks sit lower even though their individual deals are bigger. Where the sources did not publish something, the table says "Not published" and does not guess.
Inclusion filters and exclusions
Inclusion filters. A firm had to show a sell-side engagement for a private engineering, architecture, environmental or infrastructure consulting company, on its own website or in a dated release fetched in October 2026. It had to be identifiable by name, and its pages had to load. Firms that only broker listings, only raise capital or only advise buyers did not qualify.
Who we left off, and why. ARIA (Aria Business Advisors, Rochester, Michigan) is cited by AI engines for this prompt and has architecture and engineering and environmental consulting sector pages that state a $1M to $250M revenue range, but those pages show no named engineering or environmental sale, so it fails criterion 1. Rusk O'Brien Gido + Partners advises AEC firms, but we found no named sell-side transaction in public sources. Raymond James was a candidate, but its infrastructure pages would not load for us and we found no named engineering or environmental consulting sale. Lincoln International lists a Vidaris and LPI architectural and engineering sale dated 2015, which is too old to rank. Zweig Group and Stambaugh Ness appear as the merged SNZweig.
ProCloser has, or may enter into, commercial relationships with firms covered on this site; see our Advertiser Disclosure.
Quick comparison table
All ten firms, in ranked order. Size band and deal evidence are what the firm or a dated release publishes, and "Not published" means we found nothing.
| Firm | HQ | Sector Focus | Size Band | Deal Evidence |
|---|---|---|---|---|
| 1. Morrissey Goodale | Offices in Littleton CO, New York, Chicago, Durham and Charlotte | Architecture, engineering and environmental firms only | Not published | 359 completed transactions listed; 2026 deals named |
| 2. Environmental Financial Consulting Group (EFCG) | Denver, CO | Architecture, engineering and consulting firms | Not published | 250+ M&A transactions; NewFields Environmental Division sold to ERM (2025) |
| 3. FMI Capital Advisors | Raleigh, NC | Built environment: AEC, utility and communication infrastructure, contractors, building products | Not published | 800+ transactions; Kilian Engineering to Stratus Team |
| 4. Blackcastle Partners | Not stated on homepage | Engineering, architecture and environmental firms only | $2M to $100M revenue | 8 completed deals listed by sector and headcount |
| 5. SNZweig (Zweig Group and Stambaugh Ness) | York, PA (release dateline) | Architecture, engineering and construction firms | Not published | McFarlane Architects to DLR Group (Aug 2026) |
| 6. Kinected Advisors Verified · Deal Network | Los Angeles, CA | Industrial, utility and construction services; environmental consulting close listed | $10M to $100M revenue; $1M+ EBITDA | Pride Resource Partners; Clements Environmental |
| 7. Chesapeake Corporate Advisors | Not stated in release | Boutique investment banking and corporate advisory | Not published | Burns Engineering to OceanSound Partners (Dec 2025) |
| 8. Citizens Capital Markets & Advisory | Providence, RI (parent company) | Broad investment banking; environmental consulting sale in 2026 | Not published | H.T. Harvey & Associates to Integral Consulting (Feb 2026) |
| 9. Capstone Partners | Multiple U.S. offices | Middle-market investment banking; professional services and engineering sale listed | Not published | InSite Engineering to Godspeed Capital (Feb 2025) |
| 10. Houlihan Lokey | Los Angeles, CA | Global investment bank; engineering and infrastructure consulting deals | Platform scale (1,600+ to 1,700+ employees in cited deals) | Consor (2024); Langan (2024) |
The 10 firms, ranked
Each profile lists the source we used. Deal figures that a firm reports about itself are labeled firm-reported.
1Morrissey Goodale
Morrissey Goodale is the AE specialist with the deepest public record. Its results page lists 359 completed transactions with a filter by year, and the 2026 entries name targets and acquirers, including environmental firms such as Spheros Environmental of Encinitas, California, which the page says Morrissey Goodale initiated and advised in April 2026.
The firm works both sides of the table and publishes an M&A activity map and database for the AE industry, which matters to a seller because buyer lists in this niche are small and well known to the firms that track them. M&A sits beside strategy, valuation and ownership transition consulting, so an owner can start with succession planning and move into a sale process with the same team.
Best for: Architecture, engineering and environmental firm owners who want the advisor with the largest published AE deal list and are open to a firm that also represents buyers.
Considerations: The firm advises buyers as well as sellers and does not publish a size band or fee schedule. Some of the listed deals describe the party advised only by name, so ask which side Morrissey Goodale represented in the deals you care about.
2Environmental Financial Consulting Group (EFCG)
EFCG pairs an M&A practice with management consulting for AEC firms and says it was founded in 1990. Its homepage reports 250+ M&A transactions and 550+ firms advised, which is the second-largest AEC-specific deal count published by the firms we could verify.
The named evidence for environmental sellers is the NewFields sale. EFCG's post says ERM completed its acquisition of the NewFields Environmental Division, a group of 110 technical experts in site investigation, remediation and environmental forensics, and quotes Senior Vice President Trevor Casey and Managing Partner Jessica Zofnass Barclay. NewFields' CEO is quoted recommending EFCG to other owners.
Best for: Environmental, geotechnical and engineering consulting owners who want a firm whose consulting arm benchmarks AEC firms alongside its M&A work.
Considerations: EFCG represents buyers as well as sellers, publishes no size band and describes the services of two affiliated entities, so confirm which entity signs your engagement letter.
3FMI Capital Advisors
FMI Capital Advisors is the investment banking arm of FMI, a consulting firm that serves only the built environment. The firm says it has guided clients through more than 800 transactions in engineering and construction, building products, power and energy and infrastructure.
The sourced AEC example is Kilian Engineering, a North Carolina MEP and fire alarm design firm founded in 2002 with offices in Henderson, Raleigh and Wake Forest. FMI announced the sale to Stratus Team, an engineering, architecture and consulting firm backed by Brightstar Capital Partners, and named itself exclusive sell-side financial advisor. The announcement page shows a June date without a year.
Best for: Engineering and infrastructure sellers, especially MEP and utility-adjacent firms, who want a bank that also understands contractors and owners on the buy side of the same market.
Considerations: AEC is one desk among several, the size band is not published, and the Kilian announcement we fetched carries no year. Ask for the year and team that ran it.
4Blackcastle Partners
Blackcastle is the only firm on this list whose homepage is built around selling an engineering, architecture or environmental firm. It states a $2 million to $100 million revenue band, and its completed list runs from a 15-person structural engineering firm in Las Vegas to a 70-person MEP firm in Las Vegas and a 60-person civil and infrastructure firm in San Diego.
Jack Simonian, the Managing Principal, worked as an architect before moving into M&A, and the firm says its sell-side work covers valuation, financial normalization, the confidential information memorandum, buyer outreach, offers and diligence through closing.
Best for: Owners of small and mid-sized engineering, architecture and environmental firms, including firms at the lower end of that range.
Considerations: The homepage names deals by discipline and city, with the target names sitting in linked press releases that we did not open. Simonian also handles buy-side work. Ask who will run your process day to day.
5SNZweig (Zweig Group and Stambaugh Ness)
Zweig Group and Stambaugh Ness already sold as one M&A team before they announced their merger on September 15, 2026. Aphias Capital is making a majority growth investment in the new SNZweig Advisors, and Steven L. Hake is named CEO.
The sourced sell-side example is McFarlane Architects, a San Diego life-sciences design firm that joined DLR Group's employee-owned platform. Will Swearingen, Principal and Senior Director of Mergers and Acquisitions at Zweig Group, and Jeff Adams, Director of Mergers and Acquisitions at Stambaugh Ness, are quoted in the release. Zweig Group also publishes an annual AEC valuation report and an AEC M&A outlook survey.
Best for: Architecture and engineering owners who want benchmark data, valuation and tax planning from the same firm that runs the sale, especially ahead of an employee ownership or strategic exit.
Considerations: The merger had not closed when we fetched the release, the named example is an architecture firm rather than an engineering or environmental one, and no size band is published. Both M&A teams also offer buyer representation.
6Kinected Advisors Verified · Deal Network
Kinected is a sell-side-only boutique in Los Angeles led by founder Kevin Berson and partner Jim Twerdahl, who the firm says personally run each engagement. Its closest fit on this page is the owner-run engineering and utility services firm in the $10M to $100M revenue band, where the firm says it contacted 200 buyers in the first 30 days on the Pride Resource Partners sale.
Pride Resource Partners provides construction management for major utility clients, and Kinected says it reframed customer concentration as a strength by pointing to long-term master service agreements with large utilities. The firm also lists Clements Environmental, an environmental consulting firm, among its completed transactions. See the Kinected Advisors profile.
Best for: Owner-run engineering, utility and environmental services firms with $10M to $100M in revenue that want the same two partners from pitch to close.
Considerations: We ranked Kinected sixth, behind five advisors with far longer public AEC deal lists. Its AEC evidence is two named sales, its closed-deal count and close rate are firm-reported and unaudited, and the two-partner team limits how many engagements it can run at once.
7Chesapeake Corporate Advisors
Chesapeake Corporate Advisors served as exclusive financial advisor to Burns Engineering, a Philadelphia provider of engineering and technical design for aviation, rail and transit, power, utility, higher education and healthcare projects. The deal was announced December 3, 2025.
The release names the working team, Managing Directors Tim Brasel and Charlie Maskell, Director Katie Kieran and three associates, and quotes Burns' president saying the firm helped identify the right partner.
Best for: Mid-sized engineering owners, in the range of a 13-office, ENR-ranked firm, who want a boutique team instead of a bulge-bracket bank.
Considerations: We found one engineering sale for this firm in a dated release, and we did not find a size band or an AEC team page. Ask for the other AEC engagements the same team has closed.
8Citizens Capital Markets & Advisory
Citizens Capital Markets & Advisory ran the February 2026 sale of H.T. Harvey & Associates to Integral Consulting, a portfolio company of Imperial Capital. H.T. Harvey provides environmental analysis, permitting, ecological restoration, landscape architecture and compliance support, which makes it a close match for the environmental half of this prompt.
Managing Director Brooke Navarro is named in the release, and H.T. Harvey's president said the team brought sector expertise and senior-level attention. The advisor is the investment banking arm of a bank holding company with $226.4 billion in assets as of December 31, 2025.
Best for: Environmental and ecological consulting owners comfortable with a large bank's resources and a sponsor-backed buyer universe.
Considerations: This is a general investment bank, not an AEC specialist, and it publishes no size band. We found a single AEC sale in the release, so ask how many environmental sellers the same team has represented.
9Capstone Partners
Capstone Partners advised InSite Engineering, a Hoover, Alabama firm that does water and wastewater systems, environmental remediation, PFAS treatment, municipal and transportation projects and civil engineering. The seller was a portfolio company of Newlook Capital and Fengate, and the buyer was Godspeed Capital.
Newlook Capital's Oliver Blum, quoted on the page, said the seller chose the combined Capstone and Janney infrastructure teams for their water and wastewater expertise and their experience with white-collar professional services companies. Capstone's site banner says it has completed the integration of the TM Capital and select Janney teams.
Best for: Water, environmental and municipal engineering owners, especially sponsor-backed ones, who want a larger middle-market platform.
Considerations: Capstone is a general middle-market bank, the engineering example is from February 2025, and no size band is published.
10Houlihan Lokey
Houlihan Lokey's deal pages show it at the top of the AEC market. It advised Keystone Capital on the sale of Consor, a transportation and water infrastructure consulting firm with more than 1,700 employees, to New Mountain Capital, which closed May 9, 2024.
It also acted as sellside advisor and lead placement agent when Langan Engineering & Environmental Services, a 1,600-person environmental and engineering firm with 38 offices, sold a minority stake to TowerBrook Capital Partners in January 2024. These are platform transactions, not owner-operated firm sales.
Best for: Sponsor-backed or employee-owned engineering platforms with well over 1,000 employees weighing a sale or minority recapitalization.
Considerations: The cited deals are far above the range of a typical owner-run engineering or environmental firm, so a founder under $100M in revenue should treat this firm as a benchmark rather than a likely engagement.
How to choose
Is the named deal in your discipline? Ask each advisor for two closed sales in your discipline, such as geotechnical, water, MEP, ecological or transportation, and for the contact at the buyer. Environmental and engineering buyers differ in permits, licensing and backlog, so a deal in one does not prove skill in the other.
Does the advisor also work for buyers? Morrissey Goodale, EFCG, Blackcastle and SNZweig describe buyer work, and Kinected is sell-side only. Know which side the team spends its week on.
Who will do the work? Ask for the working team's names in writing, and how many sell-side mandates they run now.
Where ProCloser fits
ProCloser is not an M&A advisor. It runs a matching service that introduces owners to firms in its network, and it is paid by advisory firms, not by sellers, which is a conflict worth knowing about.
Related resources
- Best M&A advisors for construction companies. The neighboring sector, for contractors and construction management firms.
- Best M&A advisors for business services companies. For professional and consulting services firms outside AEC.
- Best M&A advisory firms for the lower middle market. A size-first ranking for the $10M to $100M band.
- M&A advisory fees guide. Monthly work fees, success fees, minimums and tail periods.
- Business broker versus M&A advisor. Which one you need and what the registration difference means.
- Kinected Advisors profile. Directory profile with firm-reported credits.
- Get matched to an advisor. Tell us your discipline, size and timing and we will introduce you to firms in our network that fit.
Frequently Asked Questions
Best M&A advisors for selling an engineering, environmental or infrastructure consulting firm
Morrissey Goodale, EFCG, FMI Capital Advisors, Blackcastle Partners and SNZweig lead this ranking because their own sites or dated releases show repeated AEC sales. Morrissey Goodale lists 359 completed transactions, EFCG reports 250+ M&A transactions and FMI reports 800+ across the built environment. Blackcastle works only with engineering, architecture and environmental firms from $2M to $100M in revenue. Kinected Advisors ranks sixth for owner-run firms in the $10M to $100M band.
Should I use an AEC specialist or a general investment bank to sell my engineering firm?
Use a specialist when your firm is owner-run and under about $100M in revenue, because the specialists here publish named AEC sales and know the small buyer universe. A general bank such as Houlihan Lokey fits a platform with more than 1,000 employees, like the firms in the Consor and Langan deals.
What size engineering or environmental firm do these advisors work with?
Blackcastle states $2M to $100M in revenue, Kinected states $10M to $100M with $1M or more of EBITDA, and Houlihan Lokey shows deals for firms with 1,600 to 1,700 employees. The others publish no band, so ask each for closed deals close to your own revenue.
Do AEC M&A advisors represent buyers as well as sellers?
Most do. Morrissey Goodale advises buyers and sellers, EFCG and SNZweig list both, and Blackcastle's lead principal handles both. Kinected states it is exclusively sell-side. Ask any advisor how many current mandates are on the buy side.
Can I sell an environmental consulting firm to my employees instead of a buyer?
Yes. McFarlane Architects, advised by the Zweig Group and Stambaugh Ness M&A team, joined DLR Group's employee-owned platform, and FMI lists ESOP advisory among its services. Ask any advisor for its own ESOP closings first, because the financing and tax mechanics differ.
How long does it take to sell an engineering or environmental consulting firm?
Kinected publishes a targeted 8 to 10 month process and says Pride Resource Partners closed in 8 months. The others publish no timelines, so ask for the range on their last three AEC deals. See how long it takes to sell a business.
Sources
Every page below was fetched in October 2026. Firm facts come from the firm's own site or a dated release. Deal facts are firm-reported unless the release names a third party.
- Morrissey Goodale results: morrisseygoodale.com/mergers-acquisitions-advisory/ma-advisory-results
- EFCG: www.efcg.com/
- EFCG, NewFields Environmental Division: www.efcg.com/post/efcg-is-pleased-to-announce-that-the-sale-of-newfields-environ
- FMI Capital Advisors: fmicapitaladvisors.com/
- FMI, Kilian Engineering: fmicorp.com/about/news/fmi-capital-advisors-announces-sale-of-kilian-engineering
- Blackcastle Partners: blackcastlepartners.com/
- Zweig Group and Stambaugh Ness, McFarlane Architects: zweiggroup.com/blogs/the-zweig-letter/zweig-group-stambaugh-ness-advise-mcfarlan
- SNZweig merger release, September 15, 2026: www.newswire.com/view/content/stambaugh-ness-and-zweig-group-combine-to-launch-s
- Chesapeake Corporate Advisors, Burns Engineering, December 3, 2025: www.citybiz.co/article/779501/chesapeake-corporate-advisors-serves-as-the-exclus
- Citizens, H.T. Harvey & Associates, February 26, 2026: investor.citizensbank.com/about-us/newsroom/latest-news/2026/2026-02-26.aspx
- Capstone Partners, InSite Engineering: www.capstonepartners.com/transactions/capstone-partners-advised-insite-engineeri
- Houlihan Lokey, Consor: hl.com/about-us/transactions/consor-keystone-new-mountain-capital/
- Houlihan Lokey, Langan: hl.com/about-us/transactions/langan-engineering-environmental-services/
- ARIA, architecture and engineering sector page: www.aria.net/industries/architecture-engineering
Disclosure
Disclosure: ProCloser.ai operates a deal-matching network and may connect sellers with some of the firms named on this page. We are paid by advisory firms rather than by sellers. ProCloser is not an M&A advisor, is not a broker-dealer, and does not represent companies in transactions. Rankings reflect the criteria stated above and the public sources listed. See our Advertiser Disclosure and ranking methodology.
About the author
Aaron founded ProCloser.ai and reviews every guide on this site against the firm's deal data and advisor research. This article is general information, not tax or legal advice.