Utilization of solar energy was significantly advanced with the invention of nonimaging solar concentrators. This has enabled practical uses of solar energy for such purposes as heating and cooling of buildings and power generation without the requirement for complicated tracking. What began as a method for efficiently collecting cerenkov light in high energy physics has become the means for producing from solar energy, high temperature for many societal applications as well as ultra-high temperature for research. This talk will describe the optical principles underlying the technology and illustrate with projects and laboratories from around the world. Examples will be drawn from a number of areas: cooling a commercial building in Sacramento, California, advanced collector development in China, NASA's plans for space propulsion by heating hydrogen, and from our own City of Chicago, a commitment to be a global leader in renewable energy production and manufacturing including solar power.