About Work4’s Team

Work4 is the leader in Facebook recruiting solutions. We help thousands of companies — including PwC, Intel, Accenture, L’Oréal, Paypal, Gap — connect with talent on social networks. Our technology transforms Facebook into a source of top quality talent, enabling enterprises to extend their employer brands, drive referrals organically and efficiently address specific profiles with targeted job ads. Our dedicated team of social recruiting experts provides ongoing best practices and advanced analytics to ensure customer success. Work4 was established in 2010 and is backed by Matrix Partners and Serena Capital.


  • Stéphane Le Viet

    Stéphane Le Viet

    Co-Founder and Chairman of the Board

    Stéphane Le Viet is the co-founder of Work4 and Chairman of the Board. Having co-founded two other successful tech companies, Stéphane brings over ten years of startup experience and HR technology expertise to Work4. Stéphane gained valuable experience early in his career at McKinsey & Company in New York, after earning his MA in Applied Mathematics from Harvard University and his BS/MS in Electrical Engineering from Ecole Polytechnique in Paris.
  • Etienne Dargniès 3

    Etienne Dargnies


    Etienne Dargnies is the CEO of Work4. He oversees the company’s daily operations and is responsible for leading product development and business strategy. With previous experience as Managing Director at Nextedia Digital Marketing Agency, he brings a unique and fresh perspective to today’s recruiting issues. Etienne studied engineering at L’Ecole des Ponts et Chaussées and entrepreneurship at HEC Paris.
  • Olivier Le Floch

    Olivier Le Floch


    As Work4′s’ Chief Technical Officer, Olivier oversees our core technology development efforts. His professional interests include computer-human interaction, data visualization & exploration, and web application design & development. Prior to joining Work4, Olivier worked as a software engineer at Fotopedia, CTO at Aziluth, and board member at DojoCrea. Olivier received his MS in Computer Science from Ecole Polytechnique and Télécom ParisTech.
  • Ron Yazzetti

    Ron Yazzetti

    Senior Sales Director of North America

    Ron Yazzetti Jr. is the Senior Sales Director of North America and has been in the recruitment industry since 2003. He’s spent time at leading companies such as Careerbuilder, Monster, Hotjobs, and Snagajob where he worked with many Fortune 500 companies on their recruitment needs. He received a culinary degree at Johnson and Wales University, but has found his passion in selling SaaS and recruitment-marketing solutions.
  • James Winfrey 2

    James Winfrey

    Vice President of Client Operations

    James Winfrey is responsible for the day to dayoperations in the US. He brings over 13 years of Human Capital Experience specializing in analytics, talent management and social/mobile recruiting. James manages the US team who is ultimately responsible for our customers and partners daily interactions. Prior to joining Work4, James spent nine years with both Monster and Indeed working in the enterprise and staffing industries. He studied business at Texas State University where he received an advanced degree in Strategic Business Management and Marketing.
  • Guillaume Laguette

    Guillaume Laguette

    Director of Marketing

    Now the Director of Marketing, Guillaume has been with Work4 since 2015. During his time here, he has been identifying and strategically assessing opportunities to create long-term value for our organization. In addition to developing key partnerships both in France and San Francisco, he also manages the Marketing Team to create valuable growth. Prior to Work4, he worked in many big French companies such as Danone and Reckitt Benckiser, as a Marketing Manager. He has a Master of Science in Marketing & Management, and graduated from KEDGE Business School.
  • Camille Cosnefoy

    Director of Operations

    Camille is the Director of Operations at Work4. He handles all advertising key features, and the setup of client solutions. Before joining Work4, Camille has worked as a Data Project Lead at fitfy-five, and in the Sales, then Marketing teams at Google. He graduated from Paris Dauphine University.

Board of Directors

  • Gautier Machelon

    Co-Founder and Board Member

    Gautier Machelon is one of Work4’s Co-Founders and currently serves as a member of our board of directors. Prior to Work4, he was the CEO of Multiposting: the leading job posting software company in France. Gautier has taught at Sciences Po, and prior to co-founding these two successful companies he was an executive recruiter at CTPartners and Heidrick & Struggles.
  • Dana Stalder

    Board Member

    Dana Stalder is a Silicon Valley based general partner at Matrix Partners, where he invests in early stage software and internet companies. Dana’s experience cuts across multiple disciplines including sales, marketing, finance, technology and product management at companies such as eBay, Netscape, PayPal and Respond.com. He has managed nimble ventures as well as 2,500-person teams. Dana joined Matrix in 2008 from PayPal, where he was a senior vice president and managed all business operations, including product, sales, marketing and technology. Dana studied business and economics at Santa Clara University.
  • Xavier Lorphelin

    Board Member

    Xavier Lorphelin is a managing partner at Serena Capital, a European investment firm which finances fast-growing and innovative companies. Xavier has more than 15 years of experience in the development and investment in technology-driven companies. He worked for 5 years in the Silicon Valley, successively for Flextronics and JSource, which he co-founded in 1997. In 2002, Xavier joined Société Générale Asset Management in France to take over the venture capital activity, following the acquisition of the incubator Kangaroo Village that he co-founded in 2000. Xavier is a graduate from Ecole Polytechnique, Ecole Nationale des Ponts et Chaussées and Stanford University.

Advisor Board

  • Matthew Brown

    Co-Founder and Advisory Board Member

    Matt was responsible for product strategy and execution for Work4′s social recruiting tools, as well as the company’s analytics and technical partnerships. He opened Work4′s first US office in San Francisco, where he also led business development and marketing initiatives. Matt studied at UC Berkeley and Oxford University before dropping out of Harvard Law School to join Work4.
  • Gokul Rajaram

    Advisory Board Member

    Gokul Rajaram serves as Product Engineering Lead at Square. Prior to joining Square, Gokul served as Director of Ads at Facebook, overseeing all of the social network’s Ads related activities. He also co-founded and served as CEO of Chai Labs which was subsequently bought by Facebook. Before Chai Labs, Gokul served as Product Management Director at Google where he was known as one of the godfathers of AdSense. In addition to his duties at Square, Gokul serves as an investor, board member and advisor at several digital media/software companies. He earned his MS in Computer Science from the University of Texas at Austin and his MBA from the Massachusetts Institute of Technology- Sloan School of Management.
  • Yuri Milner

    Advisory Board Member

    Yuri Milner is a well known Russian entrepreneur and venture capitalist. He founded investment firms Digital Sky Technologies (now Mail.ru Group) and DST Global which was one of the early investors in Facebook, Zynga and Groupon. Prior to founding the Mail.ru Group and DST Global, Yuri served at the World Bank, Alliance Menatep, and New Trinity Investments. Yuri studied theoretical physics at Moscow State University and earned his MBA at the Wharton School of Business. He was named in Fortune magazine’s list of the world’s fifty most prominent business people in 2010.
  • Clara Shih

    Advisory Board Member

    Clara Shih is the co-founder and CEO of Hearsay Social, the developer of the market leading Social Media software solution for enterprises. In addition, she serves on the Board of Directors of Starbucks Corporation. Prior to co-founding Hearsay, Clara worked at Microsoft Corporation, Google, and Salesforce.com. She is the author of “Teamspace: A Simple, Self-Recovering Workspace for Collaborative Computing” and the New-York Times featured book: “The Facebook Era: Tapping Social Networks to Market, Sell, and Innovate” which has been translated into nine languages and is used as a textbook at Harvard Business School, Stanford, and over a dozen other academic institutions. Clara earned both her BS and MS in Computer Science at Stanford University.
  • Steve Pogorzelski

    Advisory Board Member

    Steve Pogorzelski is the CEO of ClickFuel, the developer of the leading SaaS-based campaign management tool for SMBs. Prior to founding ClickFuel, Steve served as President of Monster North America, and Group President for Monster International. Other Board of Director affiliations include Morgan Goodwill Industries, StartDate Labs, OurStage.com, ClickFuel, and the Board of Visitors at the University of Wisconsin’s College of Letters and Science. Steve received his BA in Journalism/Advertising from the University of Wisconsin-Madison and is the co-author of “Finding Keepers” published by McGraw Hill.
  • William Tincup

    Advisory Board Member

    William is the CEO of HR consultancy Tincup & Co. William is one of the country’s leading thinkers on social media application for human resources, an expert on adoption of HR technology and damn fine marketer. William has been blogging about HR related issues since 2007. He’s a contributor to Fistful of Talent, HRTechEurope and HRExaminer and also co-hosts a daily HR podcast called DriveThruHR.

William is a graduate of the University of Alabama of Birmingham with a BA in Art History. He also earned a MA from the University of Arizona and a MBA from Case Western Reserve University.
  • Brian Louie

    Advisory Board Member

    Brian Louie helped build the foundation of Work4′s global sales and strategic partnership efforts from 2011 to 2014. Prior to Work4, he served in various Sales Leadership and Strategy roles at Yahoo! HotJobs and Monster Worldwide. With 13 years of experience in the online recruitment industry, he has developed a unique insight to the needs of employers and the shift to social recruiting strategies. Brian holds a BA from the University of California, Irvine.