Unfair knowledge practices easily beset our efforts to achieve health equity within and between countries. Enacted by people from a distance and from a position of power ('the centre') on behalf of and alongside people with less power ('the periphery'), these unfair practices have generated a complex literature of complaints across various axes of inequity. We identified a sample of this literature from 12 journals and systematized it using the realist approach to explanation. We framed the outcome to be explained as 'manifestations of unfair knowledge practices'; their generative mechanisms as 'the reasoning of individuals or rationale of institutions'; and context that enable them as 'conditions that give knowledge practices their structure'. We identified four categories of unfair knowledge practices, each triggered by three mechanisms: (1) credibility deficit related to pose (mechanisms: 'the periphery's cultural knowledge, technical knowledge and "articulation" of knowledge do not matter'), (2) credibility deficit related to gaze (mechanisms: 'the centre's learning needs, knowledge platforms and scholarly standards must drive collective knowledge-making'), (3) interpretive marginalization related to pose (mechanisms: 'the periphery's sensemaking of partnerships, problems and social reality do not matter') and (4) interpretive marginalization related to gaze (mechanisms: 'the centre's learning needs, social sensitivities and status preservation must drive collective sensemaking'). Together, six mutually overlapping, reinforcing and dependent categories of context influence all 12 mechanisms: 'mislabelling' (the periphery as inferior), 'miseducation' (on structural origins of disadvantage), 'under-representation' (of the periphery on knowledge platforms), 'compounded spoils' (enjoyed by the centre), 'under-governance' (in making, changing, monitoring, enforcing and applying rules for fair engagement) and 'colonial mentality' (of/at the periphery). These context-mechanism-outcome linkages can inform efforts to redress unfair knowledge practices, investigations of unfair knowledge practices across disciplines and axes of inequity and ethics guidelines for health system research and practice when working at a social or physical distance.