Aims: Therapeutic alliance ruptures, due to boundary problems, and premature dropout, from therapy, are common with clients who have a diagnosis of borderline personality disorder, limiting the effectiveness of psychological interventions. Therefore, it is hoped that researching clients' perspectives will promote therapeutic relationships that are more clinically effective with people attracting this diagnosis. The intention of this research study is to contribute to contemporary understanding of therapeutic relationships, and boundaries, from the viewpoint of clients with the diagnosis of borderline personality disorder. Literature Review: The review identified that the diagnosis of borderline personality disorder, and the topic of therapeutic boundaries, are both related to ever changing and developing cultural norms. The research literature appeared, surprisingly, virtually nonexistent in the specialist area of clients' perspectives upon boundaries. Therefore, this study offered a ground-breaking opportunity to bridge some of the fissures, between research on therapy and therapeutic practice, specifically in relation to therapeutic boundaries and borderline personality disorder. Methodology: Q methodology was used to explore discourses about borderline personality disordered participants' views regarding therapeutic boundaries. A two-stage research methodology was adopted with the first stage involving online focus groups with 19 participants. The second stage of the study, involved an online Q sort procedure with 28 participants, and was partly informed by participants' views that were generated during the online focus groups. The research emphasised the effectiveness of Q methodology, with advantages over more traditional quantitative research methods, for identifying and understanding complex beliefs about therapeutic boundaries. Findings: Four statistically distinct factors emerged from the Q methodology which represented the experiences and understandings, of therapeutic boundaries, for the participants in this study. These findings are discussed in the thesis and recommendations for therapists are outlined.