Fatigue is a multifactorial symptom that is commonly faced by patients with cancer, chronic disease, and other serious illnesses. Fatigue causes suffering across biopsychosocial domains and affects patients and their loved ones. In this article, a consortium of professionals across cancer care, physical therapy, exercise, pharmacy, psychiatry, and palliative medicine offers tips and insights on evaluating, categorizing, and addressing fatigue in the setting of serious illness. The comprehensive approach to managing fatigue underscores the importance of collaborative efforts characteristic of interdisciplinary palliative care. Prioritizing screening, diagnosing, and treating fatigue is crucial for enhancing patients' and families' overall quality of life.