The objective of this study was to synthesize literature about arts therapies therapeutic actions and the perceived effect of engaging in arts therapies. Using systematic review methods, data was synthesised from qualitative and mixed method studies that reported on arts therapies treatment for people with a diagnosis of personality disorder (Cluster B). The search yielded 167 records. 32 studies were included in the analysis. Data synthesis was conducted by using extracts from the literature search which were coded and then subject to a thematic analysis and synthesis. The thematic analysis and synthesis resulted in seven overarching themes: (1) Processing interpersonal experiences (2) Processing emotions (3) Developing agency (4) Symbolising (5) Structuring experience (6) Cognitive reappraisal (7) Developing a shared experience. This thematic synthesis provides some evidence that according to the arts therapies literature available regarding patients with a diagnosis of personality disorder, there are thematic similarities in terms of primary areas of therapeutic action and the relationship between the therapeutic action and the perceived effects of engaging in arts therapies. Our findings suggest that literature about in-session therapeutic actions focus mostly on processing interpersonal experiences and the largest frequency of coded excerpts concerning the perceived effect of engaging in arts therapies was in the area of processing emotions.