According to the city of Seattle’s planning department, only 2 percent of Seattle’s market-rate apartment units have three or more bedrooms. Most of these units available are unaffordable for middle-income families. In the 1960s, Seattle was home to nearly twice as many kids as it is today and nationwide, 1 in 3 household’s includes a child under 18 years old whereas in Seattle it is less than 1 in 5. However Seattle’s high housing prices are not the only thing pushing families out into the suburbs. Cities that support families such as Copenhagen, in the photos above, have invested in a safe, healthy and sustainable urban fabric that supports kid friendly infrastructure. Children can thus be an indicator species of a safe and healthy city. A healthy city is one where children can be free range, perceive a sense of security and feel compelled to walk, bike and play. When planners and designers choose street types and traffic situations, it is important to consider the average human dimension for all ages. A study by Gehl Architects shows the risk of accidents can be reduced by physically mixing types of traffic in the same street under the heading, “shared space”. Shared streets allow automobiles, bicycles and pedestrians of all ages the opportunity to travel side by side with good eye contact. Accidents are said to be lower because the pedestrians and bicyclists need to be extra vigilant. Mixing the modes of traffic must also prioritize pedestrians or provide appropriate traffic segregation. If we shift our urban development focus from a car-centric culture and privacy demands to a discussion about feeling safe while walking in public space, we can strengthen the life of a city and desire for public safety. If we support city life for all ages so more people walk and spend time in common spaces, the real and perceived safety will increase for all. When children and adults make their daily rounds in the city space, the space and people who use it, in turn, feel and are more protected. In Copenhagen, there are often five to six story-housing buildings where there is good visual contact between residents and street space. The ground floors are friendly and populated small shops or community gathering spaces and pedestrians, even kids, ostensibly feel comfortable recreating around their neighborhoods. Lights from the ground level shops and offices at night also help to promote a neighborhood sense of safety. Such soft edges for cities signal that the city and/or neighborhood is a welcoming child-friendly place and this life in and on the street, with mixed functions along the street and inviting edge zones, are key qualities for child friendly and thus healthy cities.