The most important thing, for motivation, is to show them the relevance to their everyday job. I find that many people just tell them that GCP has to be complied with. They also portay it as Good Bureaucratic Practice . When in fact it is an ethical and quality standard that ensures the protection of subjects and the quality of data.
It is important to challenge participants and not let them pass out with "Death by PowerPoint". The sessions should be made interactive with people being require to work together and produce a responses

Mostly I find that people need to know about the vast changes to GCP that are happening. Most people think that GCP is "old hat" and they know it already. Untrue. Think again. Lots is happening in GCP and in fact it is difficult to keep abreast of it. But they must know as it is a legal requirement.

So get them to sit up and take notice!!!