This chapter, written for undergraduate medical students and post-graduate doctors in training, presents information on how to manage fever — a case which they are likely to encounter in the future in a general practice setting. It provides details of the patients' medical history and the key findings of clinical examination, together with initial investigation results data for evaluation, and helps them develop their skills of clinical reasoning. Key questions then prompt the student to evaluate the patient, and reach a decision regarding their condition and the possible treatment plan. The chapter presents the case of a single 32-year-old Kenyan-born secretary who has flu-like symptoms with a headache and muscle pains, followed by severe coldness, shivering (rigors), drenching sweats, vomiting and flushing. On examination, the patient looks unwell. Her scleras are jaundiced and she has cervical lymphadenopathy.