Bob Dorf founded his first startup at age twenty-two and, since then, six more-two homeruns, two base hits, and three great tax losses in all, as he puts it. He's advised and/or invested in at least twenty other startups since. Dorf is often called the midwife of Customer Development, having been among the first to help Steve Blank deploy it when Steve's eighth startup, E.piphany, opened its doors with five employees in 1996. Bob's sixth startup, Marketing 1to1, helped E.piphany engage its very first customers. He later critiqued the early versions of Steve's Four Steps to the Epiphany mercilessly along the way, and they've been friends and colleagues ever since. When Bob and Steve aren't writing, he runs the K&S Ranch consultancy. Bob's deep experience consulting to Fortune 500 companies and in online marketing balance Steve's VC and software-centric experience. Bob teaches a full-semester course at Columbia Business School, Introduction to Venturing, on Customer Development and getting startups right. Entrepreneurial from the age of twelve, Bob received his last W-2 almost forty years ago, when he quit his editor's job at New York's WINS Radio to launch his first startup. Dorf+Stanton Communications, founded in his living room, grew from a staff of two-Bob and a St. Bernard-to 150+, when Bob sold it in 1989. He's counseled dozens of nonprofits probono on donor development, as well. Bob cofounded Marketing 1to1 (later Peppers & Rogers Group), an early CRM strategy firm, and drove its growth to 400+ people worldwide. As founding CEO, Dorf spearheaded major strategic customer programs at a veritable who's who of companies including 3M, Bertelsmann, Ford, HP, Jaguar, NCR, Oracle, and Schwab. He's spoken before scores of US and international audiences, and published dozens of articles including an indepth Harvard Business Review treatise. Dorf lives in Stamford, Connecticut, with his wife, Fran, a therapist and thrice-published novelist. His proudest startup by far is daughter Rachel, a psychologist who recently cofounded Bob's first grandchild, Maya Rose Gotler.