There are a couple of things.
First I'll say, to agree with Andrea's point, that even though I love what I do, I would take an amazing programmer and an urban setting with a crack in the pavement and some weeds coming through over one of my spaces in terms of the number of people you can engage. People really are the most important asset we have.
I want to go back for a second to the liability issue. Invite the actuaries to come in and have the conversation. If you do, you'll find out that they actually are interested in this conversation, because fewer people are getting injured in these spaces. For some reason we think that the insurance guys are the bogeymen, and they aren't. They're you and me, the same people we are. They have kids too, and they want what's safe and what's right.
We have to get away from risk analysis and risk assessments and get into risk-benefit analysis. We have stopped doing that in the face of a short-term focus.
If we can force that conversation, the liability thing goes away. In fact, you will find that the insurers will start to be allies for some of this stuff.
Bloomberg has the most successful program. He decided that everyone is going to have a walkable green space. He took over more than 200 school grounds and turned them into public parks. He has the terrible problem of having more people with a million bucks apiece who want to have their name on a park than he has parks to put them on. That's not our problem, but it's a nice problem to have. Hopefully we'll get there some day. These spaces work.
What do these spaces need to be to engage? It's remarkably simple. Think about the woods and about a durable way of placing them into an urban setting. Just make sure that your palette comes from within a hundred miles of where you start and you will have a pretty good level of success. Landscape architects, although I railed against them, actually are pretty good—and some of our planners—if you give them that problem and force it.