Purpose: Pressure to eliminate low-value health care is increasing internationally. This pressure has produced an urgent need to identify evidence-based methods to determine the value of allied health (AH) care, particularly to recognize when additional AH care adds no further benefits. This article reports on the published methods of determining the value of AH care. Method: We systematically scanned PubMed, MEDLINE, AMED, CINAHL, PsycINFO, and the Grey Literature Review database from inception until July 2018 for peer-reviewed English-language literature. Hierarchy of evidence and information on study design and the methods or measures used to determine the value of AH care were extracted. Results: Of 189 articles, 30 were potentially relevant; after the full text was read, all were included. Of these, 24 reported on ways of determining the value of AH care, and 6 described the optimal provision of AH episodes of care. No methods were reported that could be applied to establish when enough AH therapy had been provided. Conclusion: This review found a variety of attributes of value in AH care, but no standard value measure or methods to determine what constituted enough AH care. Repeated measurement of the standard attributes of value and costs is required throughout episodes of AH care to better understand the impact of AH care from the different stakeholders’ perspectives.