Form refers to streetscape continuity, including building setbacks, how the building meets the street, the siting of buildings, and the number and width of buildings. This is what we like to call the "hugability" of a street. If the form is off, a street can feel either aloof or suffocating. You know you’ve achieved the right proportions of setbacks, street width, and building height when it feels like the street is hugging you.

For density, we are measuring building compactness and height, not so much population density – this is particularly important in terms of making it feasible to have enough destinations to walk to within a reasonable walking distance. It can also influence the scale of city – is it for cars or people?

The relative ease of getting from one block to another and the presence of barriers to pedestrians or bicyclists within blocks. You’ve been there – if there wasn’t a fence, road, highway, insert barrier of choice between you and your neighborhood restaurant, you could totally walk there. But instead, what should be a 5-min walk takes 25min so you take the car instead. That's connectivity (or lack thereof).

The number of non-residential land uses there are to walk to - how many of one's daily needs, services, and amenities are present within a certain distance. (This is primarily what Walk Score measures).

The presence of hard and soft scape public spaces, as well as their quality and accessibility. These are often the soul and life of neighborhoods; they are the city's living rooms. Along with museums and monuments, these are the places you bring your friends and families to when they visit. 

We look at recreational facilities separately from parks and public spaces. These features get a bit more at recreational walking (as opposed to walking to get to a specific destination or for a purpose other than exercise). The literature found this to be an important determinant for physical activity, so we measure the presence of outdoor and indoor physical activity facilities as their own dimension.

Pedestrian and bike amenities refer to aspects of the built environment that make it comfortable or pleasant to be a pedestrian, including sidewalk presence and quality, seating, bike lane presence and type, street trees, etc. Along with form, these are the features that truly help distinguish car-focused neighborhoods from people-first places – they are the things that make you want to linger…

Traffic safety focuses on the quality and safety of the intersection as well as the presence of traffic calming features. These include the presence of curbcuts, crosswalk markings, traffic standards, and on-street parking. These are the features that help manage all of the mobile members of the public realm – people, strollers, bicyclists, scooters, cars, and buses.

Aesthetics goes beyond the visually pleasing; it also includes aspects of urban design that make places more dynamic and inviting. We look at the transparency of buildings, colors, outdoor dining, street trees, building maintenance, ground floor uses, etc. This is charm, character, the wow factor – the things you’ll most remember about places.

Finally, personal safety refers not to actual crime data but rather the aspects of the built environment that influence our perception of safety – these are called physical incivilities and include features like graffiti, litter, broken windows, abandoned buildings and lighting. These features actually influence walking rates more than the rates of crime incidents.