When providing clinical services for late talkers, determining an appropriate interventionist is a key early decision. Although researchers have noted the effectiveness of parent-implemented interventions for some populations, few have specifically addressed late talkers. Late talkers are of considerable interest to early service providers and parents due to limited evidence-based intervention components with this population and the notion that early language deficits are significant risk factors for many disorders. The present study purpose is to describe general features of current research and ascertain intervention providers' effectiveness. A systematic literature review resulted in eight studies reporting on seven data sets (N = 175 participants). Findings indicate treatment provided by either parents or clinicians can improve late talkers' communication skills. Parent-implemented intervention emerged as potentially more effective than clinician-directed service provision based on outcome measures of targeted skills following treatment dosage. Factors limiting generalization of these findings should be addressed in future investigations.