Todd Trapnell

Chief Operations Officer and Chief Information Security Officer

Todd Trapnell, MPP, CISSP, joined ARC in 2005. In addition to his duties as the company’s Chief Operations Officer (COO) and Chief Information Security Officer (CISO), Mr. Trapnell actively manages ARC’s deliverables and performs health care modeling and actuarial analysis for a number of ARC projects.  Mr. Trapnell is a principal investigator for the Frontier Community Health Integration Project (FCHIP) demonstration, leads ARC’s monitoring work for the Oncology Care Model, and manages ARC’s actuarial and analytic tasks for the evaluation of the Financial Alignment Initiative. Mr. Trapnell also oversees a number of short-term implementation and analytic support projects within the Center for Medicare and Medicaid Innovation and was previously the project director for ARC’s activities in support of the design, implementation, and monitoring of the Physician Hospital Collaboration and Hospital Gainsharing demonstrations.

Mr. Trapnell is an ISC2 Certified Information Systems Security Professional (CISSP). He holds a Masters of Public Policy from the University of Maryland, Baltimore County, a Masters of Science in History from the University of Edinburgh, and a dual Bachelors degree in Mathematics and History from Bowdoin College.

Dan Waldo

Vice President

Dan Waldo joined ARC as a senior economist in December 2008, after a 34-year career in the U.S. Government Civil Service. Mr. Waldo designs and implements computer models to analyze the effects of changes in health policy, and helps to support demonstration operations and evaluation through claims analysis.

Prior to joining ARC, Mr. Waldo held a number of positions in the Centers for Medicare and Medicaid Services, including acting director of the Office of Strategic Planning. His technical activities were concentrated in measurement of health care financing in general and of the Federal Medicare program in particular. Mr. Waldo was the architect of the Reagan Administration actuarial cost estimates of the Medicare Catastrophic Coverage Act drug benefit, and was part of the HCFA Office of the Actuary team providing cost estimates for the Clinton Administration health reform initiative. He has provided technical assistance to the World Bank, the World Health Organization, and the Organization for Economic Cooperation in the development of frameworks for measuring and tracking health expenditure.

Mr. Waldo holds a M.A. degree in economics from the University of Wisconsin and completed the academic requirements for a Ph.D. degree in public policy from the University of Maryland – Baltimore County.

Michele “Shelly” Windsor

Chief Financial Officer

Shelly Windsor joined ARC in 1990.  She has over 26 years of experience leading the direction and oversight of financial, administrative and human resource functions.  This includes accounting, contracts, finance, forecasting, budgeting, compliance, employee benefits, and proposal development.  She has a B.S. in business administration from Stayer College.  She completed her accounting coursework at the University of Virginia, and is a Certified Public Accountant in the Commonwealth of Virginia.

Gordon R. Trapnell


Gordon R. Trapnell is a nationally recognized expert in analyzing the feasibility and estimating the cost of private and public insurance programs. He has prepared cost estimates for major new federal insurance initiatives, providing the data needed by public officials to reach important policy decisions. His analysis has served as the basis for evaluating the major national health insurance proposals developed by the Administration and Congress.

Mr. Trapnell has extensive experience analyzing the actuarial problems faced by public sector insurance and employee benefit programs, especially Medicaid and Medicare. He has been retained by the Congressional Budget Office by every Administration in the past 40 years and by a variety of other interested parties to analyze the cost and financial impacts of major proposals to change the financing of U.S. health care.  His estimates have also been used to analyze the impact of proposals to reform small group and individual health insurance markets.

Mr. Trapnell began his actuarial career at the Life Insurance Company of Virginia. As the group actuary, he was responsible for developing the benefit package and premium rates for Virginia-North Carolina 65, an open enrollment program for senior citizens that predated the Medicare program. Prior to forming ARC, he was the senior actuary responsible for Medicare in the Social Security Administration. In this capacity, he was responsible for preparing long-range Medicare cost estimates, determining tax rates and enrollee premiums, and estimating the effect of proposed legislative changes to the program. He also assisted the staff at the Congressional Committees concerned with social insurance in proposing and drafting new legislation.

Mr. Trapnell is a Fellow of the Society of Actuaries and Member of the American Academy of Actuaries.  He holds a B.S. degree in mathematics from the University of Virginia and completed preliminary examinations for a Ph.D. in finance and health economics at the Massachusetts Institute of Technology.