Work motivation has been associated with work productivity. In health care, low motivation levels are associated with low productivity and linked to poor performance, decreased patient safety, and overall poor quality care. Hence the importance, ascribed in the literature, to clearly identifying the relationships between and among factors associated with work motivation, including work attitudes, and behaviours linked to work performance such as extra-role behaviours. Despite their importance to performance in health care, these relationships are understudied and poorly understood. The purpose of this study is to better understand work attitudes and their relationships to one another and to extra-role behaviours amongst nurses working in hospitals, the community, and long-term care settings in Ontario. This study comprises two stages: first, a scoping review focused on identifying individual-, unit-level, and organization-level characteristics that influence work motivation in health service organizations. The findings from the scoping review, augmented by a more in-depth review of the literature, aided in the development of a conceptual framework that guided the second stage of the study, to examine relationships amongst a specific set of nurses’ work attitudes - including perceptions of organizational justice, perceived organizational support, and affective commitment — and extra-role behaviours – specifically, organizational citizenship behaviours — in Ontario health care settings. In the second stage of the study, a survey was developed and administered to frontline nurses actively working in hospitals, the community, and long-term care settings in Ontario. Relationships amongst the constructs of interest were examined using structural equation modeling and path analysis. Examining the relationships of these concepts in a single model is novel, and offers insights regarding their complexity. The analyses further suggest that prior studies may be under-nuanced, and approaches to conceptualizing the concepts of perceived organizational justice and affective commitment in particular may have led to erroneous conclusions regarding their associations with perceived organizational support and organizational citizenship behaviours. This study further addresses four significant gaps previously identified in the work motivation and work behaviour literature: (1) how affective commitment relates to behavioural efforts, specifically organizational citizenship behaviours; (2) utilization of reliable and validated instruments to study work motivation; (3) use of a sufficiently large sample to have empirical support for generalizability; and (4) examination of these phenomena, among nurses, across diverse health care settings.