As bilingualism becomes less exceptional in the world, and with the growing incidence of stroke and aphasia, a better understanding of how bilingualism affects aphasia recovery is increasingly important. The present study examined the effect of intensive semantic naming therapy in three phases (Spanish, English and mixed) on within- and across-language generalization for cognates and non-cognates, in a bilingual individual with chronic, severe expressive aphasia. We hypothesized that cognates would positively influence cross-linguistic generalization, which might be more likely to occur from L2 to L1. Results indicate relative increases in confrontation naming ability in the following conditions: trained versus untrained, L1 versus L2 or mixed and non-cognates versus cognates. This participant demonstrated a pattern of results consistent with a differential recovery pattern in which presentation of treatment in both languages and training of cognates may have promoted interference, thus increasing the activation threshold, and lowering performance under these conditions. (Contains 2 tables and 5 figures.)