Second, there are questions around the nature of objectives. This model is hot on measurability. It implies that behaviour can be objectively, mechanistically measured. There are obvious dangers here - there always has to be some uncertainty about what is being measured. We only have to reflect on questions of success in our work. It is often very difficult to judge what the impact of particular experiences has been. Sometimes it is years after the event that we come to appreciate something of what has happened. For example, most informal educators who have been around a few years will have had the experience of an ex-participant telling them in great detail about how some forgotten event (forgotten to the worker that is) brought about some fundamental change. Yet there is something more.