This manual presents an overview of iodine deficiency disorders (IDD) and provides detailed instructions in the monitoring and evaluation of IDD control and prevention programs. Health and nutrition program staff working at the provincial, district and field levels in the public health sector will find this guide particularly useful. It may also be used by interested iodized salt producers and those involved in the formulation of health and nutrition policy and programs. The manual provides information on the selection of appropriate process and impact indicators and techniques on conducting IDD program assessments.