Using attachment theory as a framework to understand relationships and the dynamics of addiction, this dissertation addresses the difficulties encountered in the therapeutic relationship when both the therapist and client have an insecure attachment style. This study uses a modified systematic literature review with the use of hypothetical vignettes to demonstrate the problematic dynamics that are likely to be encountered in psychotherapy. Qualitative and quantitative research that addresses attachment styles of therapists and addicts in a therapeutic relationship will be reviewed. Attachment dynamics between therapists and addicts are conceptualised based on Bartholomew and Horowitz’s internal working models of self and other. Results highlight that insecure attachment is prominent among clients with addiction issues and in particular addicts with fearful and dismissing attachment styles are more difficult to engage in therapy. Findings indicate that insecure attachment in therapists leads to difficulties in managing negative countertransference reactions, which interferes with their ability to provide a secure base. Potential problems that may arise out of the match or mismatch between therapists and addicts insecure attachment are highlighted with particular emphasis on the development of the alliance and transference and countertransference issues. Recommendations for research highlight methodological problems and the lack of research exploring how therapist’s attachment styles may contribute to the difficulties of working with addicts.