There are a number of agility flavors available for you to compete in. Many of the organizations will allow mixed breeds to participate. Each has its own unique flavor. TDAA is for small breeds and has reduced size equipment that reflects the size of the dogs that participate. SSA concentrates on cash prizes rather than ribbons (30% of entry fees are returned as prizes) and you can take a mulligan. UKC emphasizes control and has some unique obstacles. ASCA trials are generally open to all breeds including mixed.
The links below generally point to the agility regulations for the organization. If the links break use the Information Request page to submit a website comment and let the webmaster know. Once you are at the site, you can navigate around to find more information about the organization.