This can be a company conference room, a library meeting room, or space at a restaurant. The final element is publicity. If your section has a website that is even better. Meeting notices, problem solutions, comments, and references can be exchanged this way. Discussions are greatly aided if the members have each worked on a problem and then share the solution with the group.
Many groups divide up problem sets and each member presents something at each meeting.
As the group progresses, the members often bring in supplementary materials, and the group may decide to change directions to cover other aspects. The leadership baton is often passed between the originator of the group and interested members. After the original material has been covered, several groups have found other topics of interest and continued on their own. A few years ago there were several study groups active in the Twin Cities Section, and the members came together and hosted a one-day technical conference. Some study group members have been inspired to start study groups internal to their companies.