Background Challenging behaviours are often a significant difficulty faced following acquired brain injury (ABI), for which PBS+PLUS (a Positive Behaviour Support framework) is an effective intervention. Clinicians report experiencing a range of barriers to supporting behaviour change for individuals with ABI and require tailored resources to support the implementation of PBS+PLUS. This study aimed to describe the process of co-designing a PBS+PLUS intervention guidebook and podcast series together with individuals with ABI, close-others, and clinicians, and qualitatively examine co-design experiences. Methods The Knowledge-To-Action Framework was followed to support the translation of PBS+PLUS into clinical practice. Participants with ABI (n = 4), close-others (n = 7), and clinicians (n = 3) participated in focus groups contributing to the development of a PBS+PLUS intervention guidebook and podcast series. Following completion of the groups, qualitative interviews were conducted to understand participants' perspectives of the co-design experience. Transcripts were analysed using reflexive thematic analysis. Results Co-design processes are described, and participants provided practical suggestions for co-design and the dissemination of developed resources. Two core themes encapsulating four sub-themes were identified. Firstly, 'Esteeming Experiences ' described the person-driven approach of co-design whereby participants felt supported and connected with other contributors and facilitators through sharing their perspectives. Secondly, 'Empowerment ' reflected participants' increased confidence and skills in applying PBS+PLUS. Conclusions Overall, participants endorsed the therapeutic benefits of co-design engagement and high utility of PBS+PLUS resources. This study adds to the growing literature supporting the use of co-design methodology within clinical implementation, and is inclusive of individuals with ABI, close-others, and clinicians.