This is a phase II, nonrandomized, single institution study in symptomatic, previously untreated CLL patients. Subjects will receive the study drug, lenalidomide, starting at 2.5 mg daily x 3 weeks (days 1-21) and escalating up to a target dose of 10 mg daily X 3 weeks (days 1-21) followed by 1 week off therapy (days 22-28) on a 28 day cycle. Although a maximal dose of 10 mg daily (days 1-21) will be targeted, if a patient is felt by the investigator to be benefiting from doses less than the target dose (i.e. 2.5 mg or 5 mg daily), the investigator may at his discretion choose to hold the patient at that dose without further escalation. For those patients who have progressive disease after cycle 3, further dose escalations as assessed by response and toxicity at the end of each escalated dose cycle to a maximum of 25 mg (days 1-21) will be allowed. Patients will be treated with lenalidomide until disease progression or 2 cycles past CR. (no maximum of cycles).