A baseline assessment provides information on the situation the campaign aims to change. It provides a critical reference point for assessing changes and impact, as it establishes a basis for comparing the situation before and after an intervention, and for making inferences as to the effectiveness of the campaign. Baseline assessments should be conducted before the actual campaign intervention starts so as to serve as a benchmark for examining what change is triggered by the intervention. A baseline assessment is a crucial element in formative campaign research and planning, and in any monitoring and evaluation framework.

The type of data to be included in the baseline depends on the goals the campaign aims to achieve, the theory of change underlying the campaign, and the change indicators that are defined in the monitoring and evaluation framework. Baseline information should be carried out in such a way that the same type of data can be collected after the intervention, in order to compare the results and assess the extent of change, or lack thereof.