Why this passion for exploring river gorges?You are a businessman by profession. How do you reconcile business with your spirit of adventure?How do you prepare yourself for these journeys?What's pioneering about the Tsangpo expedition?How did the expedition happen?What made it so unique?How did you manage to convince the Tibetans to undertake the journey?You say it's been a transforming experience for you. How?Did you ever fear you may not be able to spot the waterfall finally?What's been the role of National Geographic in this enterprise?