Population, Health and Environment (PHE) is an approach to development that integrates health and environmental conservation initiatives in order to seek synergistic successes for greater conservation and human welfare outcomes than single-sector approaches. PHE operates with the assumption that people, their health, and the environment are interrelated and interdependent; changes in the number, state, and/or distribution of any of the above affects the other because human needs, their livelihood and a healthy environment are linked by chains of cause and effect.
PHE approaches represent a variety of efforts to bring a holistic, integrated set of activities and services to the communities. It refers to a flexible set of interventions or activities that communities, partner groups or non-governmental organizations adopt in response to unmet community needs for improved health services, livelihoods and natural resource management. PHE projects strive to simultaneously improve access to health services and assist communities to manage their natural resources in ways that improve their health and livelihoods and to conserve the critical ecosystems upon which they depend. The underlying philosophy is fundamentally one of integration and multi-sectoral partnerships.