Initial decisions about site design are contingent upon topography, zoning and conservation restrictions. Wetlands and other natural attributes exert an influence through legal as well as physical means. The site’s character should be preserved while accommodating users and being respectful of neighbors. Pedestrians and vehicles must circulate safely. Air intake for buildings should be safely away from vehicles in order to maintain high indoor air quality. Landscape design ties a campus together and defines appropriate spaces for walking, gathering and playing. Responsible landscaping also contributes to resource conservation with sunshading, local plantings, and water filtering and reuse systems.