Free recall, use of organizational strategies, and interference effects were assessed in patients with frontal lobe lesions and control subjects. In three experiments, patients with frontal lobe lesions exhibited impaired free recall and reduced use of organizational strategies in tests of memory. Reduced use of strategies was observed on tests of recall of unrelated items, as measured by subjective organization, and on tests of recall of related items, as measured by both category clustering and subjective organization. Frontal patients benefited from strategy instruction at either study or test, suggesting that both encoding and retrieval processes are impaired by frontal lobe damage. These findings indicate that the free recall impairments exhibited by patients with frontal lobe lesions may be caused at least in part by deficits in the use of organizational strategies. In addition, when first-list learning was matched for patients and control subjects, patients with frontal lobe lesions exhibited relatively increased sensitivity to proactive interference during second-list learning.