The process of assuring that policy is carried out is in some ways the most complex of the core functions, because it is the phase at which the complexity of the partnerships that make up public health become most evident. This is also the point at which our national debate about whether there is a communal responsibility to assure access to care or whether people are really on their own once it has been determined that they are not actively transmitting diseases to others. In addition, all of the issues of business regulation and the role of government will come into play in the enforcement of health codes. Finally, we have only begun to develop the tools we need to evaluate the effectiveness and quality of services. CDC in partnership with the American Public Health Association and state and local health departments is developing, for the first time, performance standards for local public health systems. More about this effort can be learned through the CDC web site.