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Leadership

National Seating & Mobility’s management team, like our company, is geographically diverse, based in cities such as Charlotte, Chattanooga, Indianapolis, Nashville, and San Diego.

W Mixon

William Mixon

Chief
Executive Officer

WILLIAM MIXON

Chief Executive Officer

William (Bill) has 29 years of experience across the healthcare and professional services industries and more than 16 years of experience in general management, president and CEO roles. Immediately prior to joining NSM, he served as President for Universal Hospital Services (UHS), the largest provider of clinically focused asset management solutions and services involving mobile medical technology to the U.S. healthcare industry. During eleven years at Philips Medical Systems, he managed Philips’ North American service and installation businesses, consisting of nine functional business units with 3,500 employees and $1.0B+ in revenue.

Bart Witt

Bart Witteveen

Chief
Financial Officer

BART WITTEVEEN

Chief Financial Officer

Bart Witteveen joined National Seating & Mobility as Corporate Chief Financial Officer in February 2016. He is responsible for accounting/finance, billing, and collections, IT and legal. Born in The Netherlands, Bart earned his Masters (equivalent) in Business and Economics from Erasmus Universiteit (Rotterdam). Bart started his career with General Electric (14 years) where he held various finance positions in the Plastics, Healthcare and Financial services divisions in Asia, Europe, and the US. Most recently, Bart served as CFO at GetWellNetwork (MD) and Matrix Medical Network (AZ).

John Bertone

John Bertone

Executive VP
Field Operations

JOHN BERTONE

Executive VP of Field Operations

John Bertone started his 27-year history within the Rehab industry as the Founder/Co-Owner of Rehab Solutions in Columbus, OH. After growing his business in seven different markets, a strategic development company recruited John to consolidate four health care companies into a single, multi-state DME business. Bertone’s first-hand knowledge of payer/vendor relations, operating practices, and business planning makes him a great fit as NSM’s Senior Vice President of Field Operations.

Ann Mahaffey

Ann Mahaffey

Sr. VP
Human Resources

ANN MAHAFFEY

VP Human Resources

Ann brings more than 25 years’ experience to NSM, managing, developing and delivering HR strategies for large, multi-site operations including Sears & Roebuck. She is responsible for developing human capital strategies to support NSM’s corporate objectives, talent acquisition, performance management, organizational structure, total rewards programs and building a high-performance culture.

Darren Lowman

DARREN LOWMAN

Chief
Supply Chain Officer

DARREN LOWMAN

Chief Supply Chain Officer

Prior to joining NSM, Lowman served as Director of Strategic Sourcing at Tractor Supply Co., a $7 billion retailer with more than 1,700 locations. While there, he led the development and execution of a worldwide sourcing strategy. Earlier in his career, Lowman served as Vice President of Supply Chain Network at American Tire Distributors and held technical and sourcing roles with Kimberly Clark Corp. and Polymer Group, Inc., respectively.

Charles Sargeant

CHARLES SARGEANT

Sr. VP
Field Support Operations

CHARLES SARGEANT

Sr. VP Field Support Operations

Charles joined NSM in 2010 to provide leadership and management for NSM’s Southwest and West Regions. With a decade of practical experience in the HME industry and an academic background in Business Accounting, Charles is uniquely equipped to implement his patient-focused vision with NSM.

Isaac Headshot

ISAAC RODRIGUEZ

Sr. VP
Strategic Development

ISAAC RODRIGUEZ

Sr. VP Strategic Development

Isaac Rodriguez assumed VP, Northeast Region duties, following four years as area vice president for the Pacific Region. Pre-NSM, Rodriguez spent a combined 15 years with Ottobock as Director of Operations and in Revenue Management and Operations positions for Apria Healthcare.

Doug McDaniel

DOUG MCDANIEL

Sr. VP
Business Development

DOUG MCDANIEL

VP Business Development

Doug McDaniel joined NSM in 2005 after a 15-year career owning and operating a multisite Complex Rehab Technology (CRT) company. His varied experience in the rehab industry led him to be tapped to lead NSM’s national CRT network, Capstone Mobility Group. Capstone managed NSM’s contracting and business relationships with health plans on a national, regional, and even local basis, and maintained a full national provider network until 2013. Doug re-joined NSM in 2013, leading business development efforts. He also maintains responsibility for managing NSM’s health plan relationships.

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ANDY SCHIESL

VP
West Region

ANDY SCHIESL

VP West Region

Coming Soon.

JM Headshot

JASON MIELE

VP
Northeast Region

JASON MIELE

VP East Region

Jason brings 20 years’ experience in the healthcare space both clinically as an occupational therapist and a multi-site senior operator in the home health, nursing, and senior living sectors. Specializing in clinical implementation and program development, Jason seeks innovative ways to serve clients. He is responsible for the development and implementation of systems, process, and methods to ensure quality outcomes, operational excellence, growth and financial health of the Northeast Region. Jason brings unique leadership experience presently serving as United States Army Reserve Medical Officer who has held strategic positions and assignments in the Capital Region.

Derek Miller

DEREK MILLER

VP
Central Region

DEREK MILLER

VP, Central Region

Derek Miller started with NSM as a Regional Area Director with over 14 years of field experience. Prior to NSM, Derek helped grow Home Health Depot from a single site DME outlet to one of the largest CRT providers in the Midwest. Derek’s experience as a certified ATP with Lean Six Sigma training provides a unique leadership perspective to help NSM’s clients and referral sources achieve their seating and mobility objectives.

thomas lopez headshot

Thomas Lopez

VP
Southeast Region

THOMAS LOPEZ


Insert Thomas Bio Here.

Stephanie

STEPHANIE BUCKLEY

VP
Marketing

STEPHANIE BUCKLEY

VP Marketing

Stephanie Buckley joined NSM in 2017 and brings more than 20 years’ experience leading, developing and delivering brand and marketing strategies for businesses of all sizes, but most recently for The Little Clinic, a wholly-owned subsidiary of The Kroger Co.. Buckley is responsible for brand management, marketing programs, and company internal & external communications.

Kevin Harmon

KEVIN HARMON

VP
Financial Operations

KEVIN HARMON

VP Financial Operations

Kevin oversees National Seating & Mobility’s financial operations from NSM’s Chattanooga Operations Center. He is a Tennessee Technological University graduate (Cookeville, TN).

Mark Marschkel

MARK MARSCHKE

Chief
Information Officer

MARK MARSCHKE

Chief Information Officer


Mark served a five-year term as the CIO at Larson-Juhl, a Berkshire-Hathaway Company in the Atlanta area. In this role, Mark was charged with developing the multi-year technology roadmap to improve operational efficiencies, leading organizational upgrades to replace hardware, systems, and applications. He was also selected to serve on the Berkshire-Hathaway CIO Council, collaborating on technology, governance, security and business alignment for their key holdings. Throughout his career, Mark has served in key leadership roles at Matrix Resources, UPS and Coca-Cola.

NSM staff member

RYAN ZARB

VP
Technical Services

RYAN ZARB

VP Technical Services

Ryan is responsible for the development of enrichment programs for the NSM Technicians providing critical service and repair assistance to individuals with mobility challenges. He oversees the Technical Services leadership team offering guidance and support to the Technicians in the field. A certified Project Management Professional (PMP) with more than 10 years experience in various industries, he has implemented sustainable operational improvements for businesses in various industries located in Canada, the United States, Germany, and France.

Brendan_Swift

BRENDAN SWIFT

VP
Work Comp/Key Accounts

BRENDAN SWIFT

VP, Work Comp/Key Accounts


Brendan Swift started his 20 year history in health plan operational leadership roles supporting key operations functions for Oxford Health Plans, UnitedHealthcare, Coventry Health Care, First Health Network and Aetna. During his time in the payer space, he has lead service, claims and clinical operations functions, PMO, and national provider network management and contracting efforts. Swift joined NSM in September of 2015 and currently leads the NSM360 National Workers’ Compensation Program and Manages National Key Accounts.

Damaris

DAMARIS ROBLES

Director of
Operational Excellence

DAMARIS ROBLES

Director of Operational Excellence

Damaris has 27 years of experience as an expert in business transformation, driving operational change and implementing customer-centric solutions for Fortune 500 companies including Berkshire Hathaway’s, Shaw Flooring Group. She is responsible for the deployment of Lean & Six Sigma improvement methodologies and directing cross-functional projects that focus on the optimization of people, process & technology. Damaris holds a Bachelor of Science degree in Electrical Engineering from Florida State University.

Karen Shell

KAREN SHELL

Director of
Compliance

KAREN SHELL

Director of Compliance

A graduate of the University of Alabama, Birmingham, Karen Shell has been with NSM since the opening of Branch 02 in Birmingham in 1992. She moved into the General Manager position for the Alabama locations in 1998, moved to Franklin, TN to work in Operations during 2001, and assisted in the development of NSM’s first Joint Commission accreditation program in 2006. Karen is currently Director of Compliance and created NSM’s formal Compliance Program 2014.

Jeff Mat

JEFF MATUKEWICZ

General Counsel
& Secretary

JEFF MATUKEWICZ

General Counsel & Secretary

Jeff Matukewicz is the General Counsel & Secretary. He oversees NSM’s legal issues and questions pertaining to healthcare regulatory and operational matters, contracts, acquisitions, escalated collection issues, and compensations issues.

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