With increasing age, some dogs develop a neurodegenerative disease that is commonly referred to as canine cognitive dysfunction syndrome (CDS). Diagnosis of CDS can be clinical or based on laboratory tests. The main behavioral changes associated with CDS are disorientation, altered interactions with people or other animals, sleep-wake cycle alterations, housesoiling, and changes in activity level. Ruling out medical conditions that can cause similar changes in behavior is important when performing a clinical diagnosis. Management of CDS includes dietary and pharmacological intervention. Dietary treatment of CDS has been based on the use of antioxidants and mitochondrial co-factors, and recent work has shown that long-term supplementation with medium-chain triglycerides can improve cognitive function in aged dogs. CDS must be considered an animal welfare issue, and the implications of this are discussed in this paper.