Q: Should there be rigorous criteria on the selection of attendees, or should one wing it? (science or art?)
A: For many meetings, the attendees are either self-selecting or follow from attendance at a previous meeting (with maybe a few minor changes).
If you are setting up a new meeting group, however, the selection of attendees can require careful consideration. Then you should look for the right blend of skills and experience, as you would when setting up any team. You may need to canvass opinions or ask for suggestions from colleagues.
Whether you’ve made the right selection will be shown once the new group has met – and you should be prepared to be flexible and potentially adjust the attendance if the group is to continue for further meetings.