Quality data are necessary to make good decisions in health delivery, for both individuals and populations. Data can be used to improve care and achieve equity. However, the collection of health data has been weak in most impoverished countries, where health data are compiled in stacks of poorly organized paper records. Efforts to streamline and improve health information discussed in this chapter include patient-held booklets, demographic health surveys, and the use of common indicators. This chapter also focuses on the evolution of medical records, including electronic systems. The use of data for monitoring, evaluation, and quality improvement is explained. Finally, this chapter reviews the use of frameworks—such as logic models and log frames—for program planning, evaluation, and improvement.