America’s recruitment industry developed from the practice that emerged during the Second World War and was soon abandoned. It happened when entrepreneurs discovered that businesses were willing to pay well for assistance in finding suitable staff, from a temporary typist to the chief executive officer.

This venture’s pioneers created staffing and executive search companies known today as the industry’s giants. Despite the growth of specialized staffing in IT, healthcare, and technology, the industry still relies on the companies’ legacy.

The following section provides a brief description of the top 10 recruitment companies based on their founding year, owner, what they do, and the services they provide.

Quick Comparison

Rank	Company	Founded	Owner / Founders	Headquarters	Core Focus
1	Kelly Services	1946	Founded by William Russell Kelly; publicly traded (NASDAQ: KELYA)	Troy, Michigan	Staffing & Workforce Solutions
2	ManpowerGroup	1948	Founded by Aaron Scheinfeld & Elmer Winter; publicly traded (NYSE: MAN)	Milwaukee, Wisconsin	Staffing & Talent Solutions
3	Robert Half	1948	Founded by Bob & Maxine Half; publicly traded (NYSE: RHI)	Menlo Park, California	Professional Staffing & Consulting
4	Heidrick & Struggles	1953	Founded by Gardner Heidrick & John Struggles; publicly traded (NASDAQ: HSII)	Chicago, Illinois	Executive Search & Leadership Consulting
5	Korn Ferry	1969	Founded by Lester Korn & Richard Ferry; publicly traded (NYSE: KFY)	Los Angeles, California	Executive Search & Organisational Consulting
6	Allegis Group	1983 (as Aerotek)	Founded by Steve Bisciotti & Jim Davis; privately held	Hanover, Maryland	IT & Technical Staffing
7	Express Employment Professionals	1983	Founded by Bob Funk & Bill Stoller; privately held, franchise model	Oklahoma City, Oklahoma	Franchise-Based Staffing
8	ASGN Incorporated	1985 (as On Assignment)	Founded by Michael McGowan; publicly traded (NYSE: ASGN)	Glen Allen, Virginia	IT Staffing & Government Consulting
9	TrueBlue	1989 (as Labor Ready)	Founded by Glenn Welstad & Joseph Sammons; publicly traded (NYSE: TBI)	Tacoma, Washington	Blue-Collar & Industrial Staffing
10	Insight Global	2001	Founded by Bert Bean & Bert Cassidy; privately held	Atlanta, Georgia	IT & Professional Staffing

Kelly Services – The Company That Pioneered Modern Temp Staffing

 Image Courtesy: Kelly Services  / Official Website

• Founded: 1946 
• Owner: Founded by William Russell Kelly; publicly traded on NASDAQ under the symbol KELYA 
• Headquarters: Troy, Michigan

Kelly Services was founded by William Russell Kelly, starting small to fill office labour gaps in the post-war economy. It became famous through its “Kelly Girl” temporary clerical workers, a brand that helped popularise the concept of temporary staffing in America. 

The company later expanded beyond clerical work into industrial, scientific, and education staffing. It now operates across many countries worldwide. In recent years, it has shifted focus toward specialty talent and outsourcing services. This shift reflects its journey from a small clerical staffing idea to a large, diversified workforce solutions provider.

What Kelly Services does: Provides staffing, workforce management, and outsourced talent solutions for businesses across industries.

Services offered: Temporary and temp-to-hire staffing, professional and industrial placement, education and healthcare staffing, and outsourced workforce management.

ManpowerGroup – A Global Staffing Giant Born Over Lunch

 Image Courtesy: ManpowerGroup / Official Website

• Founded: 1948 
• Owner: Founded by Aaron Scheinfeld and Elmer Winter; publicly traded on the NYSE under the symbol MAN 
• Headquarters: Milwaukee, Wisconsin

ManpowerGroup was founded by Aaron Scheinfeld and Elmer Winter in Milwaukee, growing into one of the largest staffing companies worldwide. The company now operates through brands like Manpower, Experis, and Right Management. It connects workers with employers across many countries globally. 

Jonas Prising currently serves as Chairman and CEO, leading its continued global expansion. Its multi-brand structure has helped it stay one of the most globally spread staffing companies in the industry. This broad presence reflects decades of steady international growth.

What ManpowerGroup does: Provides workforce solutions spanning staffing, recruitment, training, and career management for businesses worldwide.

Services offered: Contingent and permanent staffing, professional and IT recruitment through Experis, career transition and outplacement services, and workforce consulting.

Robert Half – A Leader in Specialised Professional Staffing

 Image Courtesy: Robert Half / Official Website

• Founded: March 1948 
• Owner: Founded by Bob and Maxine Half; publicly traded on the NYSE under the symbol RHI 
• Headquarters: Menlo Park, California

Robert Half was founded by Bob and Maxine Half in New York City, built around the idea that staffing agencies could specialise deeply in a single professional field. This specialisation shaped its core divisions, including Accountemps and Robert Half Finance & Accounting. It later founded Protiviti as a dedicated risk and business consulting subsidiary. 

The company expanded into technology, legal, and creative staffing over time. It renamed itself simply “Robert Half” to reflect its broader identity. This name change mirrored its growth from a finance-focused staffing agency into a broader consulting and staffing business.

What Robert Half does: Provides specialised professional staffing and consulting services across finance, technology, legal, and creative fields.

Services offered: Accounting and finance staffing, technology and IT staffing, legal and creative professional placement, and risk and business consulting through Protiviti.

Heidrick & Struggles – A Pioneer of Modern Executive Search

 Image Courtesy: Heidrick & Struggles / Official Website

• Founded: 1953 
• Owner: Founded by Gardner Heidrick and John Struggles; publicly traded on NASDAQ under the symbol HSII 
• Headquarters: Chicago, Illinois

Heidrick & Struggles was founded by Gardner Heidrick and John Struggles in Chicago, becoming one of the first firms to treat executive search as a real profession. The firm expanded outside the Midwest early in its history. Over the decades, it broadened into leadership consulting and culture assessment. 

It remains one of the most recognised names in executive search. The firm now serves boards and senior leadership teams globally. Its early success in Chicago helped establish executive search as a lasting, respected profession.

What Heidrick & Struggles does: Provides executive search and leadership consulting services for boards and senior management teams.

Services offered: Senior executive and board search, leadership assessment and development, culture and organisational consulting, and interim executive placement.

Korn Ferry – Executive Search and Organisational Design at Scale

 Image Courtesy: Korn Ferry / Official Website

• Founded: November 14, 1969 
• Owner: Founded by Lester Korn and Richard Ferry; publicly traded on the NYSE under the symbol KFY 
• Headquarters: Los Angeles, California

Korn Ferry was founded by Lester Korn and Richard Ferry in Los Angeles, growing into one of the world’s largest executive search firms. Its acquisition of Hay Group added deep compensation and organisational design expertise to the business. Korn Ferry now combines senior leadership recruitment with broader talent and rewards consulting. 

It operates across many countries as a global talent advisory business. This integrated model sets it apart from firms that focus purely on search. It positions Korn Ferry as a full talent advisory business rather than a single-service search firm.

What Korn Ferry does: Provides executive search, leadership consulting, and organisational design services to enterprises worldwide.

Services offered: Senior executive search, leadership development and assessment, total rewards and compensation consulting, and organisational strategy advisory.

Allegis Group – The World’s Largest Privately Held Staffing Company

 Image Courtesy: Allegis Group / Official Website

• Founded: September 1, 1983, as Aerotek 
• Owner: Founded by Steve Bisciotti and Jim Davis; remains privately held 
• Headquarters: Hanover, Maryland

Allegis Group began as Aerotek, founded by Steve Bisciotti and Jim Davis, starting out by supplying technical staff for aerospace and defence clients. TEKsystems was later launched to expand into IT staffing. The group grew into the largest privately held staffing company in the United States. 

It now operates through a family of brands including Aerotek, TEKsystems, Aston Carter, and Actalent. Its scale and specialisation strategy made it a major player in technical and professional staffing. This family of brands has allowed Allegis to cover a wide range of technical and professional staffing needs.

What Allegis Group does: Provides staffing and workforce solutions spanning IT, engineering, professional services, and specialised technical talent.

Services offered: IT and technical staffing through TEKsystems, engineering and scientific staffing through Actalent, legal placement through Major, Lindsey & Africa, and outsourced workforce management.

Express Employment Professionals – A Franchise-Driven Staffing Powerhouse

 Image Courtesy: Express Employment Professionals / Official Website

• Founded: 1983 
• Owner: Founded by Bob Funk and Bill Stoller; privately held, operated through a franchise model 
• Headquarters: Oklahoma City, Oklahoma

Express Employment Professionals was founded by Bob Funk and Bill Stoller in Oklahoma City, built around a franchise model that let local owners run their own offices. This structure allowed the company to scale rapidly into smaller American cities. It grew into a nationwide network of franchise locations across multiple countries. 

Bob Funk Jr. now leads the organisation as CEO following his father’s long tenure. The franchise model remains central to how the company operates today. Its franchise-driven growth shows how a shared-brand model can scale staffing across many local markets.

What Express Employment Professionals does: Provides staffing and employment services through a nationwide network of independently owned franchises.

Services offered: Temporary and evaluation-hire staffing, professional and administrative placement, healthcare staffing, and franchise ownership opportunities in the staffing industry.

ASGN Incorporated – From Scientific Staffing to IT Services

 Image Courtesy: ASGN Incorporated / Official Website

• Founded: 1985, as On Assignment 
• Owner: Founded by Michael McGowan; publicly traded on the NYSE under the symbol ASGN 
• Headquarters: Glen Allen, Virginia

ASGN Incorporated began as On Assignment, founded by Michael McGowan with an original focus on staffing scientific and clinical research professionals. The company expanded through strategic acquisitions over the years, building out specialised IT and professional services brands. It later rebranded to ASGN Incorporated to reflect its broader technology and government services focus. 

Today it operates through divisions including Apex Systems and CyberCoders. It also runs a significant federal government contracting business. This mix of commercial and government work has broadened ASGN well beyond its original scientific staffing niche.

What ASGN does: Provides IT staffing, professional consulting, and government technology services across commercial and federal markets.

Services offered: IT and technology staffing, creative and digital marketing placement, federal government IT consulting, and cybersecurity and AI implementation services.

TrueBlue – From a Single Labour Ready Branch to a National Workforce Provider

 Image Courtesy: TrueBlue / Official Website

• Founded: July 1, 1989, as Labor Ready 
• Owner: Founded by Glenn Welstad and Joseph Sammons; publicly traded on the NYSE under the symbol TBI 
• Headquarters: Tacoma, Washington

TrueBlue began as Labor Ready, founded by Glenn Welstad and Joseph Sammons, aiming to professionalise the informal day-labour market for construction and warehouse work. The storefront model addressed a genuine gap for employers and workers alike. The company later rebranded to TrueBlue as it diversified into managed staffing and recruitment process outsourcing. 

Its brands now include PeopleReady, PeopleScout, and Staff Management. It continues to serve as a bridge between employers and workers in industrial sectors. Its evolution from Labor Ready to TrueBlue reflects a steady move from single-branch day labour to a diversified workforce group.

What TrueBlue does: Provides on-demand blue-collar staffing and managed workforce solutions for industrial and logistics clients.

Services offered: On-demand industrial and construction staffing, recruitment process outsourcing through PeopleScout, managed staffing programs, and specialised workforce solutions for events and manufacturing.

Insight Global – A Fast-Growing Specialist in IT and Professional Staffing

 Image Courtesy: Insight Global/ Official Website

• Founded: 2001 
• Owner: Founded by Bert Bean and Bert Cassidy; privately held 
• Headquarters: Atlanta, Georgia

Insight Global was founded by Bert Bean and Bert Cassidy in Atlanta, entering a staffing market already dominated by older incumbents. It built rapid growth around a highly localised branch model paired with an intensive client and candidate service culture. 

The firm grew into one of the largest privately held staffing companies in the United States. It focuses heavily on IT, healthcare, and professional staffing. Bert Bean continues to lead the company as CEO. Its rapid rise shows that a strong service-first approach can still compete with decades-old staffing giants.

What Insight Global does: Provides IT, healthcare, and professional staffing services to enterprise clients across the United States.

Services offered: IT contract and permanent staffing, healthcare and clinical staffing, government services staffing, and managed staffing programs for large enterprises.

Frequently Asked Questions (FAQs)

Which is the oldest recruitment company on this list? 

Kelly Services, founded in 1946, is the oldest company on this list, having pioneered the modern concept of temporary staffing in the United States.

Which is the largest privately held staffing company in the US? 

Allegis Group, which began as Aerotek in 1983, is widely recognised as the largest privately held staffing company in the United States, reporting $15.5 billion in revenue in 2025.

Which companies on this list specialise specifically in executive search? 

Heidrick & Struggles and Korn Ferry are the two companies on this list most specifically focused on executive search and senior leadership placement.

Which staffing company operates primarily through a franchise model? 

Express Employment Professionals is built around a franchise model, allowing independently owned local offices to operate under a shared national brand and system.

Which company began by staffing scientific and clinical research professionals? 

ASGN Incorporated, originally known as On Assignment, began in 1985 with a specific focus on staffing for scientific and clinical research roles.

Which company was originally focused on blue-collar, day-labour staffing? 

TrueBlue, originally founded as Labor Ready in 1989, built its business around on-demand staffing for construction, manufacturing, and warehouse work.

Which co-founder of a company on this list later became known for owning an NFL team? 

Steve Bisciotti, co-founder of Allegis Group (originally Aerotek), later became well known as the owner of the Baltimore Ravens.

Which companies on this list are publicly traded versus privately held? 

Kelly Services, ManpowerGroup, Robert Half, Heidrick & Struggles, Korn Ferry, ASGN Incorporated, and TrueBlue are all publicly traded, while Allegis Group, Express Employment Professionals, and Insight Global remain privately held.

Which is the newest company on this list? 

Insight Global, founded in 2001, is the most recently founded company on this list, having grown rapidly despite entering a market already dominated by older, established firms.

Why has the US staffing and recruitment industry remained dominated by companies founded decades ago? 

Long-standing staffing firms benefit from deep employer relationships, established brand trust, and large existing candidate networks built up over decades, advantages that are difficult for newer entrants to replicate quickly, even as technology continues to reshape how recruitment is delivered.

Conclusion

The top recruitment companies in the USA represent an industry that was largely created in the decades following World War II. Kelly Services and ManpowerGroup were the first to pioneer the modern temporary staffing industry, while Heidrick & Struggles and Korn Ferry established executive search as a separate profession. 

Later entrants to the field, including Allegis Group, Express Employment Professionals, ASGN Incorporated, TrueBlue, and Insight Global, all carved out a specialty niche to serve the growing demand for more diversified and specialized kinds of staffing services.

With the increasing need for alternative, specialized, and technology-driven staffing solutions, the ten companies are all well poised to continue to dominate the American staffing industry, whatever the year the reader happens to be perusing this list.