 Well, having been trained in medical physics, one of the surgeons had just got a grant from the Medical Research Council to develop an ultrasonic surgical technique, and they needed a research assistant to do the work, and so they gave me the job. I actually developed one of the first electronic focusing techniques for an ultrasonic probe. This is actually a scan of an artery in the neck, and I was one of the first people who made it possible to see how the blood flow is related to the anatomy. Ultrasound is used for surgery, and it's used for physiotherapy, it's used for drug delivery, so combining diagnosis and imaging with the actual therapy itself, so it has a whole wide spectrum of application.