Evaluation is an important part of the participation process. Planners must have some way of knowing they have achieved their objectives, and this can be accomplished in two ways: a process evaluation, or an impact evaluation. 

Process evaluation

The process evaluation examines the information and other opportunities that were made available to citizens. This type of evaluation focuses on "counting", for example, 

	the number of public hearings scheduled and the number of citizens who  attended each hearing,
	the percentage of voters who turned out for a particular referendum,  or
	the number of phone calls, letters, faxes, emails, or other correspondence received in response to a proposal or plan.

Process evaluation is best suited for more passive forms of participation where many citizens/stakeholders receive information, yet few may actually play a role in decision making. The evaluation will give some indication of how many citizens received information, and will record the number that actually "participated" by providing written or oral commentary to planners or elected officials.

Impact evaluation

An impact evaluation seeks to understand how the participation process actually influenced decisionmaking. Among other things, the evaluation might attempt to determine:

	whether stakeholders believe they played a role in decisionmaking,
	how satisfied participants were with the way the process was carried out, or
	whether the use of different participation tools and methods changed who actively participated, what decision points were reached, and the substance of those decisions.

An impact evaluation, as the name suggests, gives greater emphasis to the results of the process (as opposed to the process itself). This is much more time consuming to complete and, in most cases, can not be undertaken unless the evaluation methodology has been considered and put in place at the outset of the planning process.