Randstad Healthcare's leadership team is comprised of professionals with a broad range of expertise and years of experience in the healthcare staffing industry.

Abigail Tremble, President

As president of Randstad Healthcare, Abigail Tremble leads Randstad’s healthcare staffing practice with an eye for growing the business exponentially. Leveraging her expertise in positioning organizations for scalable growth, Tremble is poised to capture marketplace opportunities that exist within the $15B U.S. healthcare staffing market.

Tremble most recently served as executive vice president of national operations, in charge of more than 500 Randstad US General Staffing retail and on-site locations. In addition to overseeing sales, recruiting, employee development and business process improvement, she managed business performance of Randstad US’ third-largest business zone. Tremble also successfully managed operational execution of Randstad’s Spherion acquisition in 2011.

During a seven-year hiatus from Randstad between 2002 and 2009, Tremble co-founded and started a private consulting and recruiting firm, centralized and managed a national customer service operation, created two online universities, and implemented Six Sigma business process improvement programs. She started her career with Excel Temporary Services in 1998, a company later acquired by Randstad.

Tremble received her Bachelor of Arts degree in History from the University of Georgia and currently lives in Atlanta.

Melissa Knybel, RN, BSN, Vice President of Clinical Services and Quality

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Melissa is the Vice President of Clinical Services and Quality at Randstad Healthcare and responsible for the overall management of the Administration, Quality Assurance, and Housing departments. One of her biggest successes was achieving Joint Commission certification for Health Care Staffing Services in April 2005 for the then Travel and Case Management divisions, and later company-wide certification in May 2006. In addition to working closely with all of the field managers, Melissa also coordinates improvement projects, evaluates and monitors all workers compensation claims and medical malpractice issues, works with the Legal department to evaluate client contracts.

Melissa has over 10 years of experience in the medical staffing industry and over 10 years of clinical nursing experience. Prior to joining Randstad Healthcare, Melissa was employed as a Registered Nurse working in a variety of settings including a level one trauma center, a community hospital setting, and as an instructor for an Associates Degree RN Program.

Melissa received a Diploma in Nursing from Baystate Medical Center School of Nursing and went on to receive her Bachelor’s of Science in Nursing from the University of Massachusetts.  Melissa is a member of the Joint Commission Advisory Board for Health Care Staffing Services, sits on the Clinical Executive Committee of NATHO, the National Association of Traveling Healthcare Organizations, and is an active member of the Health Care Policy Council of the American Staffing Association.

Roxanne Kos, Director, National Operations

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Roxanne Kos is the Director of National Operations at Randstad Healthcare. Roxanne has been with Randstad over 18 years and most recently held the position of Senior Manager of Reporting and Business Intelligence. Throughout her tenure with Randstad, Roxanne has been responsible for front and back office processes and implementations, training and documentation, operational analysis and reporting.

Her considerable staffing and system experience has been leveraged by Randstad Healthcare and other Randstad divisions for system configurations, operational best practices and process improvements.

Roxanne received her Bachelor of Arts degree in Psychology from the University of Kansas. She is an active member of the Technology Association of Georgia and the Kansas University Alumni Association.