Senior Management

Mary A. Pittman, DrPH

President and Chief Executive Officer

A nationally recognized leader in improving community health, addressing health inequities among vulnerable people and promoting quality of care, Pittman assumed the reins at PHI in 2008, becoming the organization's second president and CEO since its founding in 1964. Her primary focus has been guiding the development of a strategic plan that builds on existing PHI program strengths to achieve greater impact on public policy and practice in public health. "In a changing environment, strategic planning is an ongoing process, not an end product," she said. Pittman's overarching goal is for PHI to become known for leadership in creating healthier communities. To this end, PHI continues to work closely with the state on many programs, including the Supplemental Nutrition Assistance Program and the California Cancer Registry. What's more, she advocates that all PHI projects take the social determinants of health into account to better address health disparities and inequities. Under Pittman's leadership, PHI has emphasized the integration of new technologies, creating Dialogue4Health.com, the online platform for conferencing and social networking that aims to build communities of interest for health. Other top priorities are: increasing advocacy for public policy and health reform, addressing health workforce shortages and the impacts of climate change on public health, and recognition of PHI as a preferred place to work. "I passionately believe that public health is an important component of health reform and has to have a stronger voice at the table," Pittman said. She strives for PHI's independent investigators to work together to achieve a synergy in which the sum of their contributions is greater than the whole.

Pittman has deep, varied and multi-sectoral experience in local public health, research, education and hospitals. Before joining PHI, Pittman headed the Health Research and Educational Trust, a Chicago-based affiliate of the American Hospital Association, from 1993 to 2007. Previously, she was president and CEO of the California Association of Public Hospitals and a director of the San Francisco Department of Public Health. Pittman has authored numerous peer-reviewed articles in scientific journals and two books. She has served on the PHI board of directors since 1996. Pittman also serves on numerous boards and committees, including the World Health Organization's Health Worker Migration Global Policy Advisory Council and the National Patient Safety Foundation's board of governors.

Mélange Matthews

Chief of Staff and Chief Operating Officer

Chief of staff and chief operating officer Mélange Matthews brings a wealth of expertise in management, planning, organizational support and policy analysis to PHI. Matthews is focused in part on ensuring PHI’s operational excellence and internal efficiency. “A strong internal foundation is vital to PHI’s success as a leading public health research, policy and advocacy organization,” Matthews said. With over two decades of public health experience, Matthews has served as the director and board chair of a number of local and statewide organizations. Matthews’ previous roles include acting director and chief operating officer for the San Francisco Mayor’s Office of Community Development, senior legislative planner for the San Francisco Department of Public Health; board member of the Regional Poison Control Center and member of the California Senate Medicaid Blue Ribbon Committee. As a consultant, Matthews has provided strategic planning and organizational support to foundations and nonprofits nationally. She has also taught critical theory and contemporary health issues at San Francisco State University. Matthews holds the degrees of Master of Public Health and Master of City and Regional Planning from the University of California at Berkeley.

James B. Simpson, JD, MPH

General Counsel

Simpson is responsible for a wide variety of legal and regulatory matters at PHI. He advises the president and CEO and the other members of the management team on major transactions, relationships with other institutions, policy development and new business initiatives. He also serves as PHI's compliance officer and assistant secretary of the corporation. "Our legal department takes its cue from the public health approach: The best problem is one that doesn't happen," Simpson said. "The best solution is simple and quick." He has more than 20 years of experience advising nonprofit organizations. A member of the State Bar of California, Simpson received his law degree from the University of California at Berkeley and his master's degree in public health from the University of California at Los Angeles.

Diana M. Pascual, MA

Vice President of Human Resources

Pascual is responsible for the strategy and execution of human resources work at PHI, where she oversees the recruitment, assessment, development and deployment of talent across the organization. Under her leadership, PHI was recently selected as one of the 50 best nonprofit organizations to work for. This reflects PHI's commitment to excellence in all areas of employee engagement, balanced work/life policies and best practices in HR services. Before being promoted to vice president, Pascual served as PHI's director of human resources for 10 years. Before joining PHI, she spent more than 15 years in the corporate world, working for Levi Strauss, General Electric and Matthew Bender Co., a legal publisher headquartered in New York. Throughout her career, she held progressively responsible leadership roles in human resources. Her work has covered recruitment, training and organizational development, compensation and benefits, labor relations/collective bargaining, and employee relations. Pascual obtained her bachelor's in psychology from the University of Santo Tomas in the Philippines and a master's in career development from John F. Kennedy University in Orinda, California.

Carmen R. Nevarez, MD, MPH

Vice President for External Relations and Preventive Medicine Advisor

A long-standing voice for the public's health, Dr. Nevarez is responsible at PHI for developing relationships with health and public health organizations and interests, incubating new project areas and public health advocacy. Dr Nevarez has over 32 years of experience as a physician and 29 years as a public health practitioner, having served as director of the Department of Health and Human Services and health officer for the city of Berkeley, California, as well as in various clinical settings, including as medical director at La Clinica de la Raza in Oakland. She is immediate past president of the American Public Health Association and past board chair of the Latino Coalition for a Healthy California and is currently on the board of Physicians for Reproductive Choice and Health. In addition, she has served state government as a member of advisory committees on Primary Care Clinics, Binational and Border Health and Multicultural Health. Her areas of expertise include community-based strategies for chronic disease prevention, women's reproductive health and social media for public health. She has been instrumental in developing and implementing a data driven strategy for advocating for teen birth prevention activities in the California Legislature.

Suzanne Petroni, PhD

Vice President for Global Health

Petroni is PHI's first vice president for global health, a position that reflects the organization's growing international thrust. With two decades of service in the government, philanthropic and nonprofit sectors, she is a respected leader, thinker and speaker on a range of global health concerns, including reproductive health and rights, adolescent health, population and women's issues, and climate change. At PHI, Petroni will be designing and implementing a global health strategic plan, expanding the organization's global health projects, managing its global health staff and recruiting new personnel. "The need to improve public health throughout the Global South is tremendous, but this challenge is being matched by the commitment of the U.S. and other world leaders," Petroni said. "With its focus on innovation, systems strengthening and community engagement, and with a particular emphasis on the health of women and girls, PHI is ideally situated to help realize this commitment through deepening and expanding its global health work." Before joining PHI, Petroni administered millions of dollars in grants for international reproductive and adolescent health and rights at the Summit Foundation. As chair of the Funders Network on Population, Reproductive Health and Rights, she led an association of more than 60 U.S.-based donors. She founded and led a consortium of foundations and bilateral and multilateral agencies to advance young people's access to sexual and reproductive health worldwide. Petroni spent nearly a decade in the federal government, working closely with various United Nations agencies, foreign governments and nongovernmental organizations. She received a master's degree in foreign service from Georgetown University and a doctorate in gender and social policy from the George Washington University School of Public Policy and Public Administration.

Matthew Marsom

Vice President for Public Health Policy and Advocacy

As PHI's first director of public health policy and advocacy, Marsom is responsible for monitoring and influencing public health policy, legislation and regulations that affect PHI projects and interests. "This new role is about moving strategically and acting as a voice for PHI on state, federal and global public policy issues that support our larger mission," Marsom said. "Given the changes in Washington, this is an opportune and exciting time to enhance our role." Marsom positions PHI to cultivate understanding and support for public health, primarily at the state legislative and administrative levels, but also as appropriate with Congress, federal agencies and community organizations. Previously, he was chief of the Policy, Partnerships and Planning Unit of the Cancer Prevention and Nutrition Section of the California Department of Public Health, providing support for policy development, legislative analysis and external relations. He also oversaw the policy and partnership activities of the Network for a Healthy California. Marsom, originally from the United Kingdom, was an advocate for community-based child care organizations and an advisor for policy and strategy within the Early Years and Childcare Unit for the Department of Education and Skills in London. He received his bachelor's degree with First-Class Honors in political science from the University of Stirling in Scotland and postgraduate certificates in Russian and research methods from the University of Glasgow in Scotland.