Fatigue (lack of energy - feeling weak, listless, tired) is a common complaint in various diseases such as anemia, malnutrition, kidney and liver diseases, cancers, infections, etc. An Indian study estimates the prevalence of chronic fatigue in 12% of Indian women. Transient self-limiting fatigue can occur in some diseases such as viral infections (e.g., flu). Chronic fatigue syndrome (Myalgic Encephalomyelitis) is a disease condition of new-onset fatigue (6 months duration) which is not due to ongoing exertion, is unrelieved by rest, and reduces various individual activities. The onset may be abrupt and precipitated by a stressful event. Other conditions associated with fatigue include malaise, muscle pains, joint pains, nonrefreshing sleep, new headache, impairment of memory, lack of concentration, dizziness, nausea, and sore throat. The symptoms fluctuate in severity, though most patients remain functionally active. Fibromyalgia and chronic fatigue syndrome can co-occur in many patients. Chronic fatigue syndrome does not progress. Most patients improve over time, although those achieving complete remission are less than 10%. Patient education, proper night-time sleep, pain relief, relaxation techniques, aerobic exercises, and behavioral therapy are critical in managing these patients.