The purpose of protected areas is to protect all natural resources and the ecosystem processes and places they depend on. Protected areas are key tools in management and policy strategies on national and international scales to combat the degradation of biodiversity and natural habitats.

Although protected areas are primarily concerned with conservation, they can also preserve places of cultural importance, mitigate climate change, maintain water supplies and provide socio-economic benefits among others. As protected areas have become integral in landscapes and seascapes around the world, work on improving the global protected areas systems and their effectiveness is fundamental to conservation practices.

Protected areas tend to be the main locations were viable populations of species are maintained and, if necessary, recovered in their natural habitat. They can also provide income and employment opportunities in rural regions through such processes as ecotourism, and form the basis for conservation education programmes. Protected areas provide invaluable locations for scientific research and monitoring to take place as well as for recreational and touristic use as leisure time grows in importance. In addition, protected areas provide immeasurable benefits by preserving and maintaining global ecosystem services that regulate the planet, and preserve natural resources for generations to come.

The functions of protected areas include:

• Scientific research 
• Wilderness protection 
• Preservation of species and genetic diversity 
• Maintenance of environmental services, such as water supplies
• Protection of specific natural and cultural features 
• Tourism and recreation 
• Education
• Sustainable use of natural resources
• Maintenance of cultural and traditional sites, including sacred areas