On Saturday I was at a workshop looking at improving the experience of pedestrians and cyclists in inner-city neighbourhoods in our city. One of the guest speakers brilliantly summed up why that horrible 1980s/90s street design style which corralled pedestrians into convoluted, fenced routes to guide them away from busy roads didn't work:
"We're natural Pythagoreans. We'll never walk around a right angle if we can see a hypotenuse."
One of my principles of embedding Sustainability into organisations is to make the sustainable option the easiest route. That means removing barriers to that hypotenuse and making the unsustainable option(s) the 'right angled' route(s).
This can be physical (like putting cycle parking by the front door) or it can be bureaucratic (making it more difficult to book flights than trains), but I have seen time and time again that it works.