Harvard Business School alum Rick Krieger and some partners decided to start QuickMedx, the forerunner of CVS MinuteClinics, after Krieger spent a frustrating few hours waiting in an emergency room for his son to get a strep-throat test. CVS MinuteClinic can see walk-in patients instantly and nurse practitioners can prescribe medicines for routine ailments, such as conjunctivitis, ear infections, and strep throat. Because most people don't want to go to the doctor if they don't have to, there are now more than a thousand MinuteClinic locations inside CVS pharmacy stores in thirty-three states.