# Top 25 professional services firms in Alexandria

Tamtam tracks 25 professional services firms headquartered in Alexandria. This list ranks all of them by number of employees on LinkedIn, led by Modern Technology Solutions, Inc. (MTSI), Systems Planning & Analysis and DCS Corp. Their median headcount is 338. Half of them were founded in 1993 or later.

These Alexandria-based companies are primarily professional services firms, many of which specialize in serving government and national security sectors. The list includes a mix of large established firms and mid-sized companies. Modern Technology Solutions, Inc. (MTSI) is an employee-owned engineering company offering technology solutions in areas like missile defense and cybersecurity. Systems Planning & Analysis provides analytical insights for national security programs. DCS Corp delivers advanced technology and management solutions to national security agencies, while Kearney & Company specializes in government financial management services.

A significant number of these firms, such as Systems Planning & Analysis and DCS Corp, focus on defense and space manufacturing or related government administration, indicating a strong cluster of companies supporting national security objectives. CALIBRE Systems, Inc. offers management consulting and digital transformation to government and industry clients. Cotton is an audit and accounting firm. The presence of companies like Culmen International, a global provider of technical and logistics services, also highlights a focus on international affairs and global operations.

🇺🇸 Alexandria · 25 companies · Updated Nov 12, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [Modern Technology Solutions, Inc. (MTSI)](https://www.tamtam.ai/c/modern-technology-solutions-inc-mtsi) (mtsi-va.com)<br>Employee-owned engineering company providing technology solutions in areas such as missile defense, cyber security, intelligence, aviation, and homeland security | Space Research and Technology | 🇺🇸 Alexandria | 2,308 | 1993 |
| 2 | [Systems Planning & Analysis](https://www.tamtam.ai/c/systems-planning-and-analysis) (spa.com)<br>Provides rigorous, objective analytical insights and innovative solutions for critical national security programs supporting US and Allied missions. | Defense and Space Manufacturing | 🇺🇸 Alexandria | 2,242 |  |
| 3 | [DCS Corp](https://www.tamtam.ai/c/dcs-corp) (dcscorp.com)<br>Provides advanced technology and management solutions to national security government agencies, emphasizing customer satisfaction and mission success. | Defense and Space Manufacturing | 🇺🇸 Alexandria | 2,043 | 1977 |
| 4 | [Kearney & Company](https://www.tamtam.ai/c/kearney-and-company) (kearneyco.com)<br>A leading CPA firm specializing in government financial management services to enhance operations, compliance, accountability, and prevent fraud | Accounting | 🇺🇸 Alexandria | 1,061 | 1985 |
| 5 | [CALIBRE Systems, Inc.](https://www.tamtam.ai/c/calibre-systems-inc) (calibresys.com)<br>A management consulting and digital transformation company serving government and industry clients with enduring solutions for management, technology, and program challenges | Business Consulting and Services | 🇺🇸 Alexandria | 784 | 1989 |
| 6 | [Cotton](https://www.tamtam.ai/c/cotton) (sikich.com)<br>A specialized audit and accounting firm offering financial, IT, and management consulting services, with a focus on work-life balance and professional excellence | Accounting | 🇺🇸 Alexandria | 434 |  |
| 7 | [Systems Planning and Analysis, Inc. (MCR LLC acquired by SPA in 2021)](https://www.tamtam.ai/c/systems-planning-and-analysis-inc-mcr-llc-acquired-by-spa-in-2021) (spa.com)<br>Providing objective analysis and solutions for national security objectives, evolving to meet client needs in defense, homeland security, and energy sectors | Defense and Space Manufacturing | 🇺🇸 Alexandria | 396 | 1972 |
| 8 | [Culmen International](https://www.tamtam.ai/c/culmen-international) (culmen.com)<br>Global provider of technical, management, humanitarian assistance, and logistics services with extensive experience operating in over 140 countries on six continents | International Affairs | 🇺🇸 Alexandria | 384 | 2004 |
| 9 | [MPR Associates, Inc.](https://www.tamtam.ai/c/mpr-associates-inc) (mpr.com)<br>An engineering and management services firm founded by naval nuclear propulsion engineers, delivering excellence in various markets globally for almost 60 years | Design Services | 🇺🇸 Alexandria | 383 | 1964 |
| 10 | [Robbins-Gioia](https://www.tamtam.ai/c/robbins-gioia) (teamrg.com)<br>The company focuses on improving depot planning and scheduling to enhance utilization, throughput, and readiness for the present and future #FutureReadinessToday | Software Development | 🇺🇸 Alexandria | 348 | 1980 |
| 11 | [Mayvin, Inc.](https://www.tamtam.ai/c/mayvin-inc) (mayvin.com)<br>Innovative culture, inclusive work environment, ongoing career development, and dedication to protecting national security with unwavering dignity and respect #PeopleMatter | Government Administration | 🇺🇸 Alexandria | 341 | 2008 |
| 12 | [ALFANAR for Recruitment شركة الفنار للتوظيف](https://www.tamtam.ai/c/alfanar-for-recruitment)<br>A recruitment company providing comprehensive services and solutions to meet all your needs (19 words) | Human Resources Services | 🇺🇸 Alexandria | 339 | 2011 |
| 13 | [Patriot Enterprises LLC](https://www.tamtam.ai/c/patriot-enterprises-llc) (patriotenterprisesllc.com)<br>Providing outstanding program support to military and government organizations globally | Business Consulting and Services | 🇺🇸 Alexandria | 338 |  |
| 14 | [Planate Management Group](https://www.tamtam.ai/c/planate-management-group) (planate.com)<br>Global provider of facilities engineering and management consulting services, specializing in responsive technical solutions for clients in various environments worldwide | Architecture and Planning | 🇺🇸 Alexandria | 302 | 2007 |
| 15 | [Pinaki](https://www.tamtam.ai/c/pinaki) (pinakitech.com)<br>Global IT services integrator offering solutions in e-finance, mobile, ERP, staffing, RPO, and more Award-winning recruitment services with expertise in business domains | IT Services and IT Consulting | 🇺🇸 Alexandria | 244 |  |
| 16 | [JB Management, Inc. (JBM)](https://www.tamtam.ai/c/jb-management-inc-jbm) (gojbm.com)<br>A Veteran Owned Small Business providing programmatic, planning, operations, maintenance, training, system integration, engineering, and information operations services worldwide | Defense and Space Manufacturing | 🇺🇸 Alexandria | 185 | 1990 |
| 17 | [Oblon](https://www.tamtam.ai/c/oblon) (oblon.com)<br>A leading law firm specializing in intellectual property law, with experienced attorneys and patent professionals helping clients protect their assets worldwide | Law Practice | 🇺🇸 Alexandria | 183 | 1968 |
| 18 | [Mekanic](https://www.tamtam.ai/c/mekanic) (mekanic.com)<br>A full-service agency specializing in branding, digital marketing, experience design, and advertising to help organizations grow and succeed | Marketing Services | 🇺🇸 Alexandria | 95 | 2015 |
| 19 | [Soft Scribe LLC](https://www.tamtam.ai/c/soft-scribe-llc) (softscribellc.com)<br>Integrated solutions provider specializing in Social Media Management, Transcription, Bookkeeping, Accounting, and Data Analytics, delivering cost-effective, reliable, and timely services nationwide | IT Services and IT Consulting | 🇺🇸 Alexandria | 25 | 2005 |
| 20 | [World Services LLC of Virginia](https://www.tamtam.ai/c/world-services-llc-of-virginia) (wsllc.com)<br>Providing a wide range of IT services including management consulting, cloud architecture, software development, data science, testing, and cybersecurity for various government and commercial clients | IT Services and IT Consulting | 🇺🇸 Alexandria | 22 | 2010 |
| 21 | [Ashley Cooper](https://www.tamtam.ai/c/ashley-cooper) (acrg.com)<br>Global strategic advisory and consulting firm offering independent advice, data analytics, valuations, investigations, transaction advisory, and regulatory consulting to various industries worldwide | Financial Services | 🇺🇸 Alexandria | 20 |  |
| 22 | [Halt, Buzas & Powell, Ltd](https://www.tamtam.ai/c/halt-buzas-and-powell-ltd) (cpas4you.com)<br>Top-rated accounting and advisory firm in Virginia and Maryland, providing expert financial services, personalized strategies, and building lasting client relationships | Accounting | 🇺🇸 Alexandria | 14 | 1969 |
| 23 | [Motley Fool Ventures](https://www.tamtam.ai/c/motley-fool-ventures) (foolventures.com)<br>Venture capital firm based in Alexandria, VA, investing in early-stage tech companies to create competitive advantages, with a focus on providing value beyond capital | Venture Capital and Private Equity Principals | 🇺🇸 Alexandria | 12 | 2018 |
| 24 | [Friedman Grimes Meinken & Leischner PLLC](https://www.tamtam.ai/c/friedman-grimes-meinken-and-leischner-pllc) (oldtownlawyers.com)<br>A full-service law firm offering expertise in family law, business law, civil litigation, criminal defense, estate planning, personal injury, and more | Law Practice | 🇺🇸 Alexandria | 9 |  |
| 25 | [473 Group](https://www.tamtam.ai/c/473-group) (473group.com)<br>Global research and strategy consulting firm specializing in risk management and procurement, providing effective solutions for businesses worldwide with confidentiality and privacy | Business Consulting and Services | 🇺🇸 Alexandria | 5 | 2016 |

## How this list is built

Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 12, 2026.

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## The same list elsewhere in United States

- [Professional services firms in the United States](https://www.tamtam.ai/l/professional-services-firms-united-states) (7,079)
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- [Professional services firms in Illinois](https://www.tamtam.ai/l/professional-services-firms-illinois) (339)
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- [Professional services firms in Georgia](https://www.tamtam.ai/l/professional-services-firms-georgia) (246)
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- [Professional services firms in Ohio](https://www.tamtam.ai/l/professional-services-firms-ohio) (195)
- [Professional services firms in Maryland](https://www.tamtam.ai/l/professional-services-firms-maryland) (176)
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- [Professional services firms in Alabama](https://www.tamtam.ai/l/professional-services-firms-alabama) (136)
- [Professional services firms in Minnesota](https://www.tamtam.ai/l/professional-services-firms-minnesota) (124)
- [Professional services firms in New York](https://www.tamtam.ai/l/professional-services-firms-new-york) (735)
- [Professional services firms in Chicago](https://www.tamtam.ai/l/professional-services-firms-chicago) (196)
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- [Professional services firms in San Francisco](https://www.tamtam.ai/l/professional-services-firms-san-francisco) (130)
- [Professional services firms in Washington](https://www.tamtam.ai/l/professional-services-firms-washington) (109)

## The same list elsewhere

- [Professional services firms in the world](https://www.tamtam.ai/l/professional-services-firms-in-the-world) (24,737)

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Source: https://www.tamtam.ai/l/professional-services-firms-alexandria