Within a framework of overlapping jurisdictions and responsibilities, the city councils (cabildos) were one of the institutions which performed various functions to protect and further public health in the Spanish American Indies. The seventeenth century records of the cabildo in Santiago, Chile, reveal that the councilmen (capitulares) not only conformed to royal law and custom but also employed the scientific knowledge available to them as they struggled against sickness and disease. Their public-spirited endeavors did not, however, preclude the occasional intrusion of selfish motives into the council proceedings. These several characteristics are discernible in the records pertaining to the prevention and control of disease, registry and review of credentials belonging to members of the medical profession, contracts negotiated with physicians, steps to inhibit malpractice, and surveillance of the local apothecary shops and the municipal hospital.