The goal of this study was to address the relationship between language proficiency, language impairment and rehabilitation in bilingual Russian-English individuals with aphasia. As a first step, we examined two Russian-English patients' pre-stroke language proficiency using a detailed and comprehensive language use and history questionnaire and evaluated their impairment using the Bilingual Aphasia Test. We then attempted to replicate and extend Kiran and Roberts' study in 2010, examining results of a primarily semantic treatment for anomia in one Russian-English bilingual patient. The patient's ability to name the trained and untrained items in both the trained (English) and untrained (Russian) languages significantly improved by achieving 100% accuracy. Finally, we examined whether improvements observed in treatment were captured by a broader language test such as the Bilingual Aphasia Test. Results are discussed with respect to factors contributing to the successful treatment and the implications of rehabilitation on assessment of language skills as a function of treatment. (Contains 2 tables and 1 figure.)