A common answer used to be "keeping vehicles moving and avoiding traffic jams".
But by now, most people involved with urban transport realise that "keeping the traffic moving" is NOT a useful goal.
Mobility, especially mobility for vehicles, is just a means to other ends. It should never be seen as an end in itself. If we make preventing congestion our goal, we are confusing ends with means.
OK. So what is the real goal of urban transport planning then?
Most of us tend to answer "accessibility"! Planning for accessibility involves trying to make it easy to REACH the things we want to (like contacts, services, goods, jobs, education).
This seems like progress. Here we have a much more coherent purpose for transport planning, right?
Unfortunately, accessibility doesn't seem to excite many people. Despite decades of lip service to accessibility planning most cities still have way too much traffic-focused transport policy.
Everyone seems to agree that accessibility is the real objective. But in practice, speeding up the traffic is what most urban traffic agencies work at hardest.
What are we doing wrong? Maybe accessibility planning seems too abstract and difficult to explain? It is hard to put into practice. Accessibility has defied efforts to measure it in practical, action-oriented ways.
The magic of great places
I wonder if PLACEMAKING offers a more compelling way forward than accessibility.
I have been excited about this since I heard Fred Kent and Kathy Madden, of Project for Public Spaces, speak at the World Cities Summit in Singapore earlier this year. I think they are onto something very important.
"A place worth loving" trumps traffic focused planning much more powerfully than the abstract idea of accessibility.
Cities that have done most to tame traffic tend to be blessed with places worth protecting. The historic city centres in Europe fit this bill. Rebellions against expressway building emerged when road projects threatened much-loved neighbourhoods in American cities from the late 1960s or Australian or Japanese cities in the 1970s.
Project for Public Spaces is working on bringing a placemaking perspective into US traffic engineering with catchphrases including 'context-sensitive design' and 'streets as places'.
I don't think placemaking replaces accessibility planning or proves it wrong. I think it gives access thinking a tangible and compelling focus to rally around.
The transforming power of these ideas shines through in this 10-minute StreetsFilms interview with Gary Toth the Senior Director of Transportation Initiatives with the Project for Public Spaces.
For those of us outside North America this video also offers some lessons on avoiding the mistakes that took the USA so far down an automobile dependent path.