Purpose: The purpose of this review was to examine the effects of aphasia therapy on language and/or communication outcome measures when treatment was initiated within four months post-onset. The review evaluated the methodological quality of relevant studies and summarised the findings of the high-quality studies according to three clinical questions about the provision of aphasia treatment in the early period of recovery: (1) Is treatment better than no treatment? (2) Is one type of treatment more effective than another? (3) Do different treatment intensities result in different outcomes? Methods: A literature search was performed for articles in which aphasia treatments were initiated fewer than four months post-aphasia onset and evaluated with a control or comparison group. Two authors rated the studies on defined methodological quality criteria and extracted data for addressing the clinical questions. Results: A total of 23 studies met the inclusion criteria. Sixteen of the studies received high-quality ratings. Nine studies provided data addressing clinical question 1; however, only four of them were considered as high-quality studies. Results from the high-quality studies were mixed: two studies demonstrated treatment efficacy for early aphasia therapy, and two studies found no differences in outcome measures between participants who received treatment and a no-treatment control. Eleven studies provided data addressing clinical question 2; six of them were considered as high-quality. None of the eleven treatment-comparison studies found that one type of treatment resulted in greater gains compared to another type of treatment on primary outcome measures. Finally, six studies contributed data for addressing clinical question 3; all of them were considered as high-quality studies. Five studies found no significant difference in outcomes between participants assigned to lower- and higher-intensive weekly treatment schedules, and one study reported superior findings in outcomes when participants received less intensive treatment. Conclusion: This review found mixed results across studies that examined whether early aphasia treatment improved language/communication outcomes more than no treatment. The review also found that when different types of aphasia treatments were compared, no treatment was more efficacious than another treatment and that increasing the weekly intensity of treatment beyond 2–5 hours did not improve outcomes on language/communication measures. The review highlights the need for additional research on the effects of early aphasia therapy. We suggest that future research considers participant characteristics that might influence how a person will respond to a specific therapeutic approach and intensity.