Anyone can call themselves a "behaviorist".
An Associate Certified Applied Animal Behaviorist is certified by the Animal Behavior Society (ABS) and whose formal education (completed post-graduate education), experience (residency in a formal behavior program), and adherence to ethical standards qualify them as an expert in the field of applied animal behavior.
ABS maintains the highest standards for certification of applied animal behaviorists. Currently, there are approximately 50 Certified Applied Animal Behaviorists worldwide.
Certified Applied Animal Behaviorists are analogous to human psychologists but with expertise in animal behavior problems. They often work in tandem with clients’ veterinarians when medications are needed.