Evaluation types and timing

Evaluations can be conducted at different times. They can be carried out before, during or after a policy intervention has taken place. In each of these cases, they serve different purposes.

  • Ex-ante evaluations are conducted before the intervention is implemented. The ex-ante evaluation may challenge the clarity with which the objectives have been set out, as well as the plausibility of the objectives themselves.
  • 'Interim' or 'intermediate' evaluations are conducted at some point during the implementation of a programme/intervention, at a point where some early results should be apparent.
  • Ex-Post evaluations are undertaken after a programme or intervention is completed, or at least near enough to the end that most activities can be examined and the immediate outcomes assessed.
Evaluations can be formative, i.e. intended to improve performance, most often conducted during the implementation phase of projects or programs, or summative, i.e. conducted at the end of an intervention (or a phase of that intervention) to determine the extent to which anticipated outcomes were produced.