Prudence or practical wisdom canvasses the sequential pattern, which leads from a patient’s ailment to a medical intervention. This chapter outlines medicine’s prudential objectives as well as distinctions between needs and demand. Medical needs are prudentially minded, and medical care is essentially a prudential activity relying on need for intervention, namely prevention, care, or cure. Personal demands or preferences usually do not provide a foundation for proper medical interventions. Medical need is objective, extensional and prudentially minded, while medical demand is subjective and intensional, and provide no foundation for medical intervention. Medical need can be approached from a first person, a second person and a third person account.