Acupuncture has been used to treat diseases in animals for thousands of years. For the past several decades, as the use of acupuncture has increased in countries where modern Western medicine is the foundation of health care, there has been increasing scientific effort to evaluate this ancient medical treatment for objective evidence of efficacy. Clinical trials with controlled clinical conditions using either a controlled randomized or non-randomized group approach with statistical significance established for a treatment has increased among veterinary researchers. This review presents recent clinical trials involving the use of acupuncture in animals. The studies which are organized into broad categories of pain control, neurologic disease, gastrointestinal disease, disorders of sense organs and emergency medicine demonstrate its effectiveness in treating a wide range of medical conditions such as canine hip dysplasia, pain from osteoarthritis and surgery, intervertebral disc disease, seizure disorders, vomiting, inflammatory bowel disease, cardiac and respiratory depression and anxiety.