Abstract: The present invention relates to compounds useful as inhibitors of protein kinases, such as inhibitors of GSK-3. The invention provides pharmaceutically acceptable compositions comprising the compounds of the invention and methods of using the compositions in the treatment of various disorders. The invention provides processes for preparing compounds of the invention. The invention provides methods of identifying compounds useful for treatment of diabetes, diabetic neuropathy, osteoporosis, Alzheimer's disease, Huntington's disease, Parkinson's disease, AIDS-associated dementia, bipolar disorder, amyotrophic lateral sclerosis, multiple sclerosis, schizophrenia, leukocytopenia, cardiomyocyte hypertrophy, stroke, post-stroke, spinal cord injury, traumatic brain injury, Charcot-Marie-Tooth, peripheral nerve regeneration, and rheumatoid arthritis.