Mostly liability insurance (in addition to any personal policies) and ability to fly with certain clubs and/or certain fields. Some city parks require AMA membership as it carries the insurance. I considered joining just so I could fly at a dedicated field until I saw the field. It was crap. There are also two levels of memberships. There is a cheaper model that helps with the park flyers only. If you're just flying recreation only, it might work.Is anyone an AMA member? What are some of the benefits?