When we're designing new products, services or businesses, the only time you'll know if they're any good, if the designs are good, is to see how they're used in the real world, in context. I'm reminded of that every time I walk past Highbury Fields in north London. It's absolutely beautiful. There's a big open green space. There's Georgian buildings around the side. But then there's this mud trap that cuts across the middle. People clearly don't want to walk all the way around the edge. Instead, they want to take the shortcut, and that shortcut is self-reinforcing. Now, this shortcut is called a desire path, and it's often the path of least resistance. I find them fascinating, because they're often the point where design and user experience diverge. Now at this point, I should apologize, because you guys are going to start seeing these everywhere. But today, I'm going to pick three I find interesting and share what actually it reminds me about launching new products and services. The first is in the capital city of Brazil -- Brasilia. And it reminds me that sometimes, you have to just focus on designing for a real need at low friction. Now, Brasilia is fascinating. It was designed by Niemeyer in the '50s. It was the golden age of flying, so he laid it out like a plane, as you can see there. Slightly worryingly, he put most of the important government buildings in the cockpit. But if you zoom in, in the very center of Brasilia, just where the point is there, you see it's littered with desire paths. They're absolutely everywhere. Now, they thought that they had future-proofed this design. They thought in the future we wouldn't need to walk anywhere -- we'd be able to drive -- so there was little need for walkways or pavements. But as you can see, there's a real need. These are very dangerous desire paths. If we just pick one, in the middle, you can see it crosses 15 lanes of traffic. It won't surprise you guys that Brasilia has five times the pedestrian accident rate of your average US city. People are resourceful. They'll always find the low-friction route to save money, save time. Not all these desire paths are dangerous, I was reminded flying here when I was in Heathrow. Many of us get frustrated when we're confronted with the obligatory walk through duty-free. It was amazing to me how many people refused to take the long, meandering path to the left, and just cut through to the right, cut through the desire path. The question that's interesting is: What do designers think when they see our behavior here? Do they think we're stupid? Do they think we're lazy? Or do they accept that this is the only truth? This is their product. We're effectively co-designing their product. So our job is to design for real needs at low friction, because if you don't, the customer will, anyway. The second desire path I wanted to share is at the University of California. And it reminds me that sometimes the best way to come up with a great design is just to launch it. Now, university campuses are fantastic for spotting desire paths. I think it's because students are always late and they're pretty smart. So they're dashing to lectures. They'll always find the shortcut. And the designers here knew that. So they built the buildings and then they waited a few months for the paths to form. They then paved them. (Laughter) Incredibly smart approach. In fact, often, just launching the straw man of a service can teach you what people really want. For example, Ayr Muir in Boston knew he wanted to open a restaurant. But where should it be? What should the menu be? He launched a service, in this case a food truck, and he changed the location each day. He'd write a different menu on the side in a whiteboard marker to figure out what people wanted. He now has a chain of restaurants. So it can be incredibly efficient to launch something to spot the desire paths. The third and final desire path I wanted to share with you is the UNIH. It reminds me that the world's in flux, and we have to respond to those changes. So as you'll guess, this is a hospital. I've marked for you on the left the Oncology Department. The patients would usually stay in the hotels down on the bottom right. This was a patient-centered organization, so they laid on cars for their patients. But what they realized when they started offering chemotherapy is the patients rarely wanted to get in cars. They were too nauseous, so they'd walk back to their hotels. This desire path that you see diagonally, formed. The patients even called it "The Chemo Trail." Now, when the hospital saw this originally, they tried to lay turf back over it, ignore it. But after a while, they realized it was an important need they were meeting for their patients, so they paved it. And I think our job is often to pave these emerging desire paths. If we look back at the one in North London again, that desire path hasn't always been there. The reason it sprung up is people were traveling to the mighty Arsenal Football Club stadium on game days, from the Underground station you see on the bottom right. So you see the desire path. If we just wind the clock back a few years, when the stadium was being constructed, there is no desire path. So our job is to watch for these desire paths emerging, and, where appropriate, pave them, as someone did here. Someone installed a barrier, people started walking across and round the bottom as you see, and they paved it. (Laughter) But I think this is a wonderful reminder as well, that, actually, the world is in flux. It's constantly changing, because if you look at the top of this image, there's another desire path forming. So these three desire paths remind me we need to design for real human needs. I think empathy for what your customers want is probably the biggest leading indicator of business success. Design for real needs and design them in low friction, because if you don't offer them in low friction, someone else will, often the customer. Secondly, often the best way to learn what people really want is to launch your service. The answer is rarely inside the building. Get out there and see what people really want. And finally, in part because of technology, the world is incredibly flux at the moment. It's changing constantly. These desire paths are going to spring up faster than ever. Our job is to pick the appropriate ones and pave over them. Thank you very much. (Applause)