As office manager of Willamette Writers, a non-profit writers group, I often get calls asking about critique groups. I advise people to think of them as coming in four types:
Support groups generally offer encouragement in writing or marketing, and little or no critique. Some support groups also operate as social networks, and might involve eating a meal together or meeting at a restaurant.
Light Critique groups could have a format for critique, like a time limit to respond; or limits on the person responding; or a requirement that a critique start and end with a positive comment, etc. This is something a group works out. A group might have a moderator to make sure the guidelines are followed.
This is generally for writers who are published or who are interested in mainstream publishing. People read something and offer a no-holds barred critique. The author takes it in and does what they want with what is offered.
Orson Scott Card developed this idea, that an author can give a spouse or friend guidelines for how to respond to a manuscript (for example, when someone started skipping pages or lost interest). A good resource for getting good feedback from casual readers.
Where to Meet
Some people meet at a home; others meet at a Starbucks (some do close at 6 pm); some people meet at a local restaurant (3-6 is often a quiet time for a restaurant, and they appreciate people coming in; this is also a typical Happy Hour time for lower costs for food). A few groups sign up to meet at the WW Writing House
What to Look For
I advise people to try 2-3 groups to find a group that offers the right fit and personalities. Cynthia Whitcomb belongs to both a support and critique group to meet her needs.
Some people call the office and want to join a critique group (or be mentored by) New York Times best-selling authors. Those kind of people are generally protective of their time.
Finding a group that works for you could take some time and effort, but the rewards can be worth it. Even a group with prickly personalities that don't accept feedback on their work might offer you the feedback you need. Just don't get 'stuck' in a group that doesn't work for you.
Bill Johnson is the author of A Story is a Promise & The Spirit of Storytelling, available on Amazon Kindle
for $2.99 and on Smashwords