Monitoring and evaluation (M&E) can be defined as the systematic collection, analysis, and use of data to answer questions about program performance and achievements. An M&E system encompasses all the activities related to setting up, collecting, reporting, and using program information. A robust, well-functioning M&E system can provide program stakeholders with the information necessary to carry out a responsive and successful program intervention and is therefore a critical tool for program management. There are many tools and techniques needed for successful M&E of sexual and reproductive health (SRH) programs. These include frameworks to visually depict the organization of the program, its context and goals, and the logic of its M&E system. Essential practices of M&E also include continuous stakeholder engagement, the development of indicators to measure program activities and outcomes, the collection and use of data to calculate the indicators, and the design and implementation of evaluation research to assess the benefits of the program. Over time, language around “M&E” has evolved, and multiple variations of the phrase are in use, including “MEL” (monitoring, evaluation, and learning), “MER” (monitoring, evaluation, and reporting), and “MERL” (monitoring, evaluation, research, and learning), to name but a few. These terms bring to the forefront a particular emphasis of the M&E system, with an apparent trend toward the use of “MEL” to emphasize the importance of organizational learning. Despite this trend, “M&E” continues to be the most widely known and understood phrase and implicitly includes activities such as learning, research, and reporting within a robust system.