The modern pharmacist is responsible for the quality of the drugs compounded for and dispensed to a patient. The pharmacist also is responsible for helping to ensure that a drug program is appropriate for a patient, based partly on how much detailed and timely knowledge of the patient's condition is at hand. Pharmacy is a service within the health-care system that is related to drugs, their preparation, and their proper use to treat illness by cure, control, and prevention. The drug product must meet many requirements related to stability, safety, and effectiveness. Most drugs marketed today are mass-produced by the pharmaceutical industry, although the apothecary of earlier times was entirely responsible for making drugs.