In Virginia Beach, Virginia (USA), where we lived once upon a time, there was a weekly Monday morning missions meeting. It was called “7-Ms” (which stood for a long string of Ms, and I’ve forgotten what they all were). The meeting was held in the back room of a restaurant. Each time we had a speaker–usually a missionary passing through, or someone returning from a short-term trip. The purpose of the meeting was to connect people who had a heart for missions, and to encourage that mission vision.
Similar meetings are held in other cities around the country (and, I imagine, in cities in other countries). Some of them are weekly, and some are monthly. Recently, one of the founders of 7-Ms moved to Dallas, Texas (where we live now), and we met over Thai noodles to discuss starting up a similar meeting here. (There is one already being held quarterly on the Fort Worth side, but the Dallas-Fort Worth metroplex is big enough for more than one (arguably, more than two).
I share here some of the steps we are taking to start the regular meeting, in the hopes that it might help you get one started in your city.
1. You need a core group interested in seeing the meeting happen. It doesn’t have to be large. We had three sitting at the table. The core group gives you connections into the churches, agencies, and other groups within the city. This group will also be the ones responsible for identifying and solving problems, and sending out emails to let people know when the meeting will happen.
2. You need to expressly define the vision and purpose of the group.
3. You need to be willing to reach out into the community and invite others to take part in the meetings. It doesn’t have to be a big beginning. When 7-Ms first started, it was two guys sitting at a table, praying for missions; then a third joined them, then a fourth. It slowly grew to an average attendance of a dozen-to-twenty.
4. You need to be able to draw different speakers throughout the year. This is where being in a larger city, with multiple churches with missions programs and possibly a Perspectives event, is helpful. 7-Ms simply suggests in a weekly email:

As usual, if you know of anyone involved in missions passing through or someone who lives here and has done missions work, let me know and I’ll contact them about speaking to us. Also, if you know folks with a heart for missions, let them know about 7Ms and encourage them to come and be blessed. We are up to 210 on this e-mail announcement!

5. You need to have a place to meet, and a regular schedule. 7-Ms uses a restaurant, so it’s a “neutral” ground–with no perception of being “owned” by one specific ministry. Other meetups go ahead and use a church.
6. You need to have some speaker guidelines. The TED Speaker Guidelines are one hilarious way this is done. I’m not suggesting you use these, but you need to have some.
I am starting a page on JustinLong.org to index mission meet ups. If you know of one that’s happening on a regular basis, either email me or post a comment on the page.