During the 1960s, an upstart Minnesota company, Control Data, made an enormous impact on the computer industry with the help of a handful of engineers and executives led by William Norris and Seymour Cray. The rise of Control Data from a company selling stock at $1 a share to a multi-national firm manufacturing the world’s fastest computers is an extraordinary story in itself. But author Donald M. Hall also examines how the success of Control Data primed the pump of local investment and facilitated the flowering of a medical device industry that still flourishes in the state. He follows the careers of Norris and Cray, but also of Earl Bakken and Manny Villanova; he describes the changing world of computer sales, but also the ups and downs experienced by ordinary investors as firms producing innovative products sought out new investors willing to fund further research. It’s a brisk and fascinating read, a portrait of a heady time, with lessons for today’s investors.