Background: Traditional aphasia therapy is based primarily on repetition and drill. Recent treatment studies have suggested that communication-based interactions may be at least as effective if not more so in achieving positive outcomes. Aims: This study was undertaken to directly compare the outcomes of drill-based vs. communication-based interactions in modified Constraint-Induced Aphasia Therapy. Methods & Procedures: Two women with chronic non-fluent aphasia participated sequentially in two distinct treatment protocols designed to improve verb production in sentences. Both treatment protocols were provided in an intensive schedule, 30 hours over four weeks each. The treatments contrasted drill-based vs. communication-based interactions between the client and the clinician. Outcome measures included verb naming and production of personal narratives. Outcomes & Results: Drill-based but not communication-based treatment had a small positive effect on participants’ verb naming accuracy. The communication-based protocol, but not the drill-based treatment, had a pronounced positive effect on participants’ sentence and narrative structure. Conclusions: The results suggest that communication-based interactions are more effective than drill in improving narrative production in aphasia. We suggest that this type of communication-based constraint-induced therapy works to reduce learned non-use patterns of language production and can be structured to improve production of verbs in sentences. The success of this approach can be attributed to the fact communication- based therapy, like typical verbal interactions, emphasises exchange of novel information and allows individuals with aphasia to capitalise on their preserved discourse knowledge.