Ben Davis had just completed an intensive course in Statistical Thinking for Business Improvement, which was offered to all employees of a large health maintenance organization. There was no time to celebrate, however, because he was already under a lot of pressure. Ben works as a pharmacist's assistant in the HMO's pharmacy, and his manager, Juan de Pacotilla, was about to be fired. Juan's dismissal appeared to be imminent due to numerous complaints and even a few lawsuits over inaccurate prescriptions. Juan now was asking Ben for his assistance in trying to resolve the problem, preferably yesterday!