The document Integrated Disease Surveillance and Response Technical Guidelines, Booklet Four: Sections 8 and 9 (Third Edition, 2019) provides guidance for strengthening public health surveillance and response systems in the WHO African Region. It focuses on monitoring, supervision, evaluation, and feedback mechanisms to improve the performance and quality of Integrated Disease Surveillance and Response (IDSR) systems. The text outlines key surveillance core functions—such as case detection, reporting, data analysis, outbreak investigation, preparedness, response, and feedback—and introduces indicators to measure system effectiveness, including timeliness, completeness, and data quality. Additionally, it discusses the implementation of electronic IDSR (eIDSR) to enhance real-time reporting and outbreak management. Overall, the booklet aims to strengthen early detection, rapid response, and health security capacity across all levels of the health system.