The timing and duration of the evaluation will in part depend on other factors such as availability of funding and staff but primarily it should take place when it will be most effective. It has been suggested that the earlier evaluation is undertaken the greater the potential for it to impact upon the project outcomes.
Summative Evaluation – Evaluation taken at the end or after the project has finished to prove something.
Formative Evaluation – Evaluation taken during the project to improve what is being done.
Impact Studies – Reviews carried out from six months to a year after the project to assess the impact the project has had.
Development projects benefit from a balance between some formative aspects with summative elements to establish the worth of what has been achieved. Some projects end in failure, as in they do not achieve what was planned. Formative evaluation offers some protection against failure and it should certainly provide evidence about why it happened. Equally, exploratory projects may discover that a promising product or process is in fact unsuitable and this needs to be evidenced as much as success.