Background: Integrated knowledge translation refers to researcher and research user partnerships to co-generate and implement knowledge. This type of partnership may be critical to success in increasing knowledge use and impact, but the conceptualisation of its initiation has not been fully developed. Initiating this type of partnership has proven to be challenging but crucial to its success. The purpose of this study was to conduct a meta-narrative review of partnership initiation concepts, processes, enablers, barriers and outcomes in the disciplines of healthcare and social sciences where examples of researcher and research user partnerships were found. Methods: Seven research traditions were identified. Three were in the discipline of social sciences (including psychology, education and business) and five were in the discipline of healthcare (including medicine, nursing, public health, health services research). Searches were conducted in MEDLINE, EMBASE, CINAHL, ABI Inform, ERIC, PsychInfo and the Cochrane Library on June 9, 2017. Fifty titles and abstracts were screened in triplicate; data were extracted from three records in duplicate. Narratives comprised of study characteristics and conceptual and empirical findings across traditions were tabulated, summarised and compared.Results: A total of 7779 unique results were identified and 17 reviews published from 1998 to 2017 were eligible. All reviews identified a partnership initiation phase referred to as 'early' or 'developmental', or more vaguely as 'fuzzy', across six traditionsintegrated knowledge translation, action research, stakeholder engagement, knowledge transfer, team initiation and shared mental models. The partnership initiation processes, enablers, barriers and outcomes were common to multiple narratives and summarised in a Partnership Initiation Conceptual Framework. Our review revealed limited use or generation of theory in most included reviews, and little empirical evidence testing the links between partnership initiation processes, enablers or barriers, and outcomes for the purpose of describing successful researcher and research user partnership initiation. Conclusions: Narratives across multiple research traditions revealed similar integrated knowledge translation initiation processes, enablers, barriers and outcomes, which were captured in a conceptual framework that can be employed by researchers and research users to study and launch partnerships. While partnership initiation was recognised, it remains vaguely conceptualised despite lengthy research in several fields of study. Ongoing research of partnership initiation is needed to identify or generate relevant theory, and to empirically establish outcomes and the determinants of those outcomes.