The examples of the specific surveillance performance indicators which follow deal with vaccine-preventable diseases, especially regarding surveillance for measles, and for Acute Flaccid Paralysis (AFP) to detect cases of paralytic poliomyelitis. This class of diseases were selected because it is the one in which surveillance performance indicators have been most extensively developed. Nonetheless, many of the indicators can also be applied to assessing the performance of surveillance systems focused on environmental and occupational exposures, chronic diseases, injuries, and health promotion and disease prevention behaviors.