The National Complete Streets Coalition states that:
“Complete Streets are for everyone. They are designed and operated to enable safe access for all users… [so that] pedestrians, bicyclists, motorists, and public transportation users of all ages and ability are able to safely move along and across [the street].” 
The New Jersey Department of Transportation (NJDOT) expands this definition by noting that Complete Streets:
“[balance] the needs of drivers, pedestrians, bicyclists, transit vehicles, emergency responders, and goods movement.” 
Similarly, the American Association of Retired Persons (AARP) states that Complete Streets are:
“designed for the safety and comfort of all road users, regardless of age and ability.” 
Complete Streets are not defined by a single design prescription but rather the method of “completing” the streets responds to local needs and context (e.g. roadway type, topography, natural features, density of development, adjacent land use, and street connectivity). Additionally, it is emphasized that Complete Streets represent a fundamental shift in the auto-centric approach to the decision making process so that “all users are routinely considered during the planning, designing, building, and operating of all roadways.”
What are the Components of Complete Streets?
Although the design of Complete Streets depends greatly on local context, a variety of elements are frequently in the design process. The Philadelphia Complete Streets Design Handbook provides an extensive list of design elements categorized by seven street “components” :
- Pedestrian Component: defined as “the clear area located between the curb and the adjacent building frontage” . Key Complete Streets design elements for this component include appropriate sidewalk widths and ADA accessible curb ramps
- Building and furnishing: refers to “street furniture, elements of buildings that intrude into the sidewalk, and commercial activities that occur on the sidewalk…” and includes design elements such as bicycle parking, pedestrian-scale lighting, benches/street furniture, and street trees
- Bicycle: addresses “bikeways and other facilitates within the public right-of-way…” and includes design elements such as bicycle lanes (regular, buffered, contraflow, etc.), cycle tracks, share-use paths, shared lanes/sharrows, and bike route signs
- Curbside Management: relates to “facilities between the cartway and the sidewalk” and includes design elements such as on-street car parking, on-street bicycle parking, loading zones, and transit shelters.
- Vehicle/Cartway: describes the “portion of the public right-of-way that is intended primarily or exclusively for motor vehicle use…”  and includes design elements such as appropriately sized lane widths, speed humps/tables, raised medians, chicanes, and preferred/exclusive bus lanes
- Urban Design: addresses “policies related to those aspects of urban form that affect Complete Streets” such as driveways, utilities, and stormwater management.
- Intersection & Crossing: includes treatments that “…facilitate safe movement of all modes at intersections”  including high-visibility crosswalks (striped, raised, etc.), curb extensions, pedestrian refuge islands, bike boxes, and a variety of signal treatments (e.g., pedestrian countdown clocks, HAWK/RRFB signals, bicycle signals, etc.).
 National Complete Streets Coalition. “Complete Streets: Fundamentals.” www.smartgrowthamerica.org/complete-streets/complete-streets-fundamentals.
 New Jersey Department of Transportation. 2012. “Making Complete Streets a Reality: A Guide to Complete Streets Policy Development.” pg. 2
 American Association of Retired Persons. 2009. “Planning Complete Streets for an Aging America.” pg. viii.
 New Jersey Department of Transportation. 2012. “Making Complete Streets A Reality: Implementation and Design Workshop for County and Local Governments.” Slide 65.
 LaPlante, John N., Barbara McCann. 2011. “Complete Streets in the United States.” Transportation Research Board. pg. 6.
 City of Philadelphia. 2012. “Philadelphia Complete Streets Design Handbook.” pg. 67.