The consensus views of an expert roundtable meeting are presented as updated management guidelines for using alemtuzumab in chronic lymphocytic leukemia. Since the publication of previous management guidelines in 2004, clinical experience with alemtuzumab has grown significantly, especially regarding its efficacy and safety, management of cytomegalovirus (CMV) reactivation, identification of patient subgroups likely to benefit from alemtuzumab therapy and subcutaneous administration of alemtuzumab. The updated recommendations include (1) alemtuzumab monotherapy can be safely used as first-line therapy; (2) suitable patient subgroups for alemtuzumab therapy include elderly patients, patients with 17p deletion, patients with refractory autoimmune cytopenias and patients with profound pancytopenia at baseline due to heavily infiltrated bone marrow; (3) alemtuzumab treatment should be continued for 12 weeks (36 doses) whenever possible, and bone marrow examination may be considered at week 12 to evaluate response; (4) monitoring CMV reactivation by weekly PCR is mandated during therapy; when CMV reactivation becomes symptomatic or viremia increases, alemtuzumab therapy should be interrupted and anti-CMV therapy started; (5) subcutaneous administration is safe, easy to perform and appears equally effective compared with intravenous infusion and (6) our strong recommendation is that alemtuzumab combination therapy and consolidation therapy shall not be used outside carefully controlled clinical studies.