Current World Population
Net Growth During Your Visit


William Ryerson is the Population Institute's Chairman of the Board and Chief Executive Officer.  Ryerson, who also serves as President of the Population Media Center, has a 45-year history of working in the field of reproductive health, including three decades of experience adapting the Sabido methodology for behavior change communications to various cultural settings worldwide. He has also been involved in the design of research to measure the effects of such projects in a number of countries, one of which has led to a series of publications regarding a serialized radio drama in Tanzania and its effects on HIV/AIDS avoidance and family planning use. He also serves as President of the Population Media Center, which works in partnership with the Population Institute. He received a B.A. in Biology (Magna Cum Laude) from Amherst College and an M.Phil. in Biology from Yale University (with specialization in Ecology and Evolution). Before founding Population Media Center, he served as Director of the Population Institute's Youth and Student Division, Development Director of Planned Parenthood Southeastern Pennsylvania, Associate Director of Planned Parenthood of Northern New England and Executive Vice President of Population Communications International. As a graduate student, he was Founder and first Chairperson of the Yale Chapter of Zero Population Growth (ZPG). He also served on the Executive Committee of ZPG, as Eastern Vice President and Secretary of the national organization. Mr. Ryerson is listed in several editions of Who's Who in the World, Who's Who in America and Who's Who in the East. In 2006, he was awarded the Nafis Sadik Prize for Courage from the Rotarian Action Group on Population and Development.

Robert Walker is the President of the Population Institute, where he directs the organization's advocacy and public education activities, including its work on issues related to health, economic development, sustainability and the environment.

Prior to joining the Population Institute in February 2009, Mr. Walker was President of the Population Resource Center. He formerly was the Executive Director of the Common Cause Education Fund, a nonpartisan, nonprofit organization working to promote open, honest and accountable government.

He also served for three years as President of Handgun Control, Inc. and the Center to Prevent Handgun Violence, and four years as legislative director at Handgun Control, where he led the lobbying campaigns that led to the successful passage of the Brady Law and the federal assault weapons ban. Prior to his work for Handgun Control, Mr. Walker worked for a total of 14 years on Capitol Hill, including five years as a legislative aide to Rep. John B. Anderson and six years as Legislative Director to Rep. Mo Udall, the Chairman of the House Interior Committee. He also served for two years as Legislative Counsel for the American Association of Retired Persons.

Mr. Walker received his B.A. in Economics from Rockford College and his J.D. from the University of Illinois School of Law.  He attended the University of Sydney in Australia under a Rotary graduate fellowship.

Jennie Wetter is the Population Institute's director of public policy. Before working at PI Jennie was an editorial policy intern at the Renewable Natural Resources Foundation (RNRF). At RNRF she worked on various renewable resource issues and the foundation's journal, the Renewable Resources Journal. Jennie also spent time working on two of RNRF's Congresses, one on Emerging Water Contaminants, which looked at issues such as pesticides, pharmaceuticals and personal care products, fire retardants like polybrominated diphenyl ethers, and nanotechnology. The other congress was on environmental science issues facing the U.S. Congress and natural resources agencies. Jennie earned her BA at University of Wisconsin, where she majored in Biological Aspects of Conservation and had the opportunity to study abroad in Kimana, Kenya, examining human-wildlife conflict around the Kimana Community Wildlife Sanctuary. Jennie also received a Masters degree from American University's School for International Service in Washington, DC, where she majored in Global Environmental Policy, focusing on international environmental and development issues. Jennie wrote her thesis in the emerging field of environmental peacemaking looking at the peace building potential of peace parks, using the Greater Limpopo Peace Park in Mozambique, South Africa, and Zimbabwe as her case study.