Objective: The authors compared the effectiveness of 2 intensive therapy methods: Constraint-Induced Aphasia Therapy (CIAT; Pulvermuller et al., 2001) and semantic therapy (BOX; Visch-Brink & Bajema, 2001). Method: Nine patients with chronic fluent aphasia participated in a therapy program to establish behavioral treatment outcomes. Participants were randomly assigned to one of two groups (CIAT or BOX). Results: Intensive therapy significantly improved verbal communication. However, BOX treatment showed a more pronounced improvement on two communication-namely, a standardized assessment for verbal communication, the Amsterdam Nijmegen Everyday Language Test (Blomert, Koster, & Kean, 1995), and a subjective rating scale, the Communicative Effectiveness Index (Lomas et al., 1989). All participants significantly improved on one (or more) subtests of the Aachen Aphasia Test (Graetz, de Bleser, & Willmes, 1992), an impairment-focused assessment. There was a treatment-specific effect. BOX treatment had a significant effect on language comprehension and semantics, whereas CIAT treatment affected language production and phonology. Conclusion: The findings indicate that in patients with fluent aphasia, (a) intensive treatment has a significant effect on language and verbal communication, (b) intensive therapy results in selective treatment effects, and (c) an intensive semantic treatment shows a more striking mean improvement on verbal communication in comparison with communication-based CIAT treatment.