Journal Circles are similar to round robins. In a circle, a group gets together and exchanges artwork in rotation. You will work on someone elses project at the same time another artist is working on your project. In the end everyone has a completed book or a collection of pages centered around a particular theme.
I have participated in several altered book circles and am about to start a new circle where we will exchange ATC's. The theme this time is about ourselves and the things we love. So every month I will send off a photo of something I love and that artist will create an ATC using the photo for inspiration. At the same time someone will be sending me a photo of something they love and I will be creating a personalized ATC for them. The next month we each send to a different person. When the circle is complete we will all have a collection of 12 ATC's inspired by things we love and created by our fellow artists.
These are very interesting and fun to do. I would encourage you to start your own group. I would love to hear about any you have been in or especially if this inspires you to start your own circle.