Cognitive dysfunction syndrome (CDS) is a common, yet underdiagnosed, neurobehavioral disease of domestic animals. Much like its human counterpart, Alzheimer’s disease, CDS is the result of neuronal loss and inflammatory changes in the central nervous system; however, the specific pathophysiology of the disease continues to be researched in efforts to advance diagnostics, prognosis, and treatment. Diagnosis is typically conducted by ruling out possibilities and using assessment tools, including the Canine Dementia Scale and the Canine Cognitive Dysfunction Rating Scale. Treatment is often most successful when a tailored, multimodal approach is initiated early in the disease progression.