Policy, Systems, and Environment

A Policy, Systems, and Environment (PSE) change approach goes beyond simply addressing clinical interventions to improve community health.  PSE expands the reach of prevention efforts by looking at health from a population stand point.  Instead of focusing on preventing or changing individual behaviors, PSE looks at how a community, government, workplace, school, and home can be adjusted to effect change in a multitude of persons.  PSE works through three avenues of change to address the social determinants, structural determinants, and environmental determinants of health.


When public health professionals take a policy approach to making population level changes, they aren’t just looking to change laws.  A policy can be any rule, law or guideline that impacts how institutions or organizations operate.  By adjusting a rule or guideline, public health professionals can change how an entire system and environment operates.  For example, shared-use agreements allow spaces such as school playgrounds to be open to the entire community after school hours.  A policy clarifying shared-use for public schools eases the process.  Learn more about shared use policy from our New York Shared-Use Agreement Policy Guide.


Systems change is often the most difficult of the three.  Systems are entrenched in our society, and often require multiple levels to work together to create a difference.  System change can often be targeted by coalitions, policies, or committees working together.
Chronic disease often addresses food systems.  For example, a country-wide initiative called Farms to Schools links local farms and their produce to school cafeterias.  This food system change enables schools to receive healthy fresh produce at reasonable prices.  The normal food system that puts farmers and schools at two ends often results in processed food or lower-quality foods.  When farms link directly to schools, schools can choose their produce without any processing.  See more on this from our Food Procurement Fact Sheet.


Environmental changes are changes to the public’s surroundings.  This can include transportation, outdoor space, indoor space, grocery store access and interiors, and many more.  Changing the environment in a community can have impressive effects on health.

Complete Streets is an example of environmental change to increase physical activity.  Complete Streets works to make travel modes accessible to all users.  The model works by addressing all aspects of transportation, including improving bike paths to increase biker safety, adding benches on sidewalks for rest breaks for senior citizens, and adding trees to improve the aesthetics.  These changes have been shown to increase community use of multiple forms of travel.  Learn more about Complete Streets.