Useful in courses on entrepreneurship, this case describes the founding and start-up years (1949-62) of Medtronic, Inc., one of the world's leading medical-technology companies, specializing in implantable and interventional therapies. Focusing on one of the company's cofounders, Earl Bakken, the case examines entrepreneurial thinking and principles?"effectual reasoning." See also "What Makes Entrepreneurs Entrepreneurial?" (UVA-ENT-0065).