Savings Groups (SGs) are community-managed groups typically of 15-30 people who get together regularly to save and eventually borrow if they choose to. SGs are successful in large part because they depend on commitment savings: members support each other in achieving their financial goals through saving regularly. Also, a well-functioning Savings Group can be a good platform for introducing new ideas in health, agriculture, solar lighting, or many other areas to the members. Here's a short primer on informal finance by Kim Wilson (and me? I see my name on it. Hm...) and the classic introduction to savings groups: Savings Groups: What are they? by Hugh Allen and David Panetta. Both documents are solid, but both are aging and ready for an update.
Savings Groups are easy to form and easy to train. Just follow the instructions in the documents we link to below. If you conscientiously respect this material, you will do a great job. Really.
To start with, look at the basics of forming Savings Groups (SG MANUALS). If you are thinking of including SGs in a program that does other things, like agriculture or health, check out Combining Savings Groups and Other Activities. Finally, if you are interested in encouraging relations between SGs and banks or MFIs or SACCOs, be sure to look at Promoting Relations between Savings Groups and Financial Service Providers.
These are our recommendations - but of course think for yourself and see what other people say. Start with these, and then be sure to read the section on Protecting Savings Groups and their Members.