This chapter contains sections titled: Introduction Questions Literature‐search strategy and inclusions How is the diagnosis of CLL made? What is the clinical relevance of newly identified prognostic factors? What is the optimal approach to the initial treatment of patients with CLL? How should patients with relapsed or refractory disease be managed? References Introduction Questions Literature‐search strategy and inclusions How is the diagnosis of CLL made? What is the clinical relevance of newly identified prognostic factors? What is the optimal approach to the initial treatment of patients with CLL? How should patients with relapsed or refractory disease be managed? References