Open spaces in urban environments, such as parks, playgrounds, and natural areas, can provide many health, cultural, recreational, and economic benefits to the communities nearby. However, access to open spaces can be unequal for people of different incomes. In California's two largest metropolitan regions, Los Angeles County in Southern California and the Bay Area in Northern California, access to green space and natural areas varies with the predominant races and classes of the communities. This also holds true in San Diego County in Southern California. Both expanding urbanization and diminishing funding for open space tend to widen these gaps in accessibility. Because open space is associated with various mental and physical benefits, a lack of access to it can pose health consequences. However, more research is needed to determine whether such environmental inequalities translate into long-term health inequalities, and, if so, how.

There are many benefits of open space. Access to open space has been shown by studies to positively correlate with physical activity levels, provide cultural exchange and cohesion, present recreational opportunities, stimulate economic productivity, and provide environmental benefits to counter the effects of climate change in surrounding neighborhoods.

Green spaces indirectly influence the physical activity levels in a community. The accessibility of green space for citizens has been shown to directly correlate to their physical activity levels. Lower levels of physical activity leads to many health consequences, such as heart disease, obesity, and depression. For example, teenagers without access to a safe parks report significantly less exercise and worse physical health than their counterparts with access to a park. Anger and aggressiveness are often alleviated with increased time in open space. Additionally, psychological benefits increase with species richness of urban green spaces, implying that quality, not just access, affects the health benefits of natural parks in urban environments. Studies have found that pregnancy outcomes improve when pregnant women have access to a park or natural preserve, and people with easy access to national and local parks have higher-quality sleep.

Open spaces can be accessed by a diverse group of people in an urban community, allowing greater community cohesion as well as cultural exchange and interaction. Many native people have close ties to open space and often find them historically and culturally significant. Additionally, open space often serves as a source of inspiration to many in a community; for example spurring cultural creativity in the form of arts and literature. Cultural events are often held at parks. These include dances, films, and music festivals. Parks can serve to further the education of children in the community by allowing them to learn by experience and play. They allow children to avoid social problems, such as gang violence and vandalism, commonly associated with cities, and to play with peers and become aware of their community's events and political structures. Crime is often mitigated with increased open space, because people become less aggressive with increased exposure to nature. Conversely, letting spaces remain barren and failing to make them into parks or community spaces often increases crime.

Open spaces serve as places where people in the community can meet and socialize through a wide array of various activities; this includes accessing food by fishing and hunting, enjoying biodiversity by observing wildlife, and exercising by walking or hiking. These recreational opportunities can be applied to any age group; kids may be educated and can play at parks while adults can find positive community at parks. Urban parks serve as places where sports games can be held, and often attract recreation by integrating paintings, museums, zoos, memorials, and cultural centers into their designs.

Open spaces generate revenue through increasing local tourism, businesses, real estate values, and jobs, and decrease the many costs of diseases associated with nature deficit disorder. However, poorly managed parks often decrease local real estate values. The economic stimulus to real estate values potentially serves to raise tax revenue, part of which can be used to develop more parks, a positive feedback loop. The stimulus to real estate is most evident in dense urban areas since these areas are most in need of such spaces. Open spaces within developments also increase their walkability and serve to stimulate real estate prices. Recreational industries are often attracted to areas with open space because they present major sales opportunities. This further enhances job growth and opportunity, and potentially stimulates workers' talent and productivity because close access to nature increases their quality of life. It also keeps wealthy retirees in the community who may serve as a continuing source of income or social buffer. If forests are present, their harvests also may serve as a sustainable source of income to the local economy. Parks also may serve to economically revitalize a failed or defunct commercial area within a community. Open space naturally executes processes such as stormwater management and flood control, which can limit public costs from catastrophic weather events.

Open spaces provide environmental benefits to both local residents and wildlife. Due to climate change, heat waves are becoming more frequent and intense. These heat waves can be mitigated by parks through a reduced heat island effect. The air temperature in parks tends to be cooler than the air temperature in urban environments and this cool air may spread to nearby neighborhoods, reducing the need for air conditioning on hot days. Parks can also help mitigate urban pollution through air filtration by trees and UV radiation through shade provided by tree canopies. Parks limit the environmental damage of heavy storm-induced floods and filter pollutants from water before it enters streams and groundwater. Even small community parks may serve as refuges for wildlife that do not need significant amounts of continuous habitat to survive, and connections across parks allow larger fauna to survive as well. These environmental and health benefits associated with parks are estimated to be worth billions of dollars annually.

However, although parks reduce air pollution, certain demographics and low income areas may experience higher levels of pollution in parks; a study based in Los Angeles found that children in Hispanic dominated neighborhoods had higher levels of exposure to NO₂ and particulate matter than their counterparts. The researchers notes that physical activity, which often occurs in open spaces, could increase the risk that these park air pollutants are inhaled, leading to serious health consequences.