The literature on the roles of management accountants (MAs) indicates a poor understanding of these roles. There is limited, and fragmented evidence of the factors shaping these roles, contradictory findings on MAs providing meaningful information, and on adopting the model of the ‗business partner‘. There is a dearth of research on the consequences of these roles. Some of the literature is of a normative, professional bent and lacks theoretical import. From a theoretical perspective, this study employs the theories of management control, contingency, and role theory as devices through which to understand these roles. The aim of the study is to investigate the antecedents, characteristics, and consequences associated with the roles of MAs, and to analyse the extent that antecedents and characteristics associated with the roles of MAs have consequences for assisting operating managers (OMs) in the performance of their roles. The setting for the study is medium and large manufacturing firms. The first phase of data collection involved an inductive set of interviews with 18 finance managers (FMs) and 18 OMs. The second phase of data collection involved an in-depth investigation of 12 MAs as ‗cases‘ linked to specific OMs, drawing on 36 interviews and the analysis of over 50 management accounting reports. The phase one findings provide evidence of a range of antecedents, characteristics, and consequences associated with the roles of MAs. The antecedents of management and the individual MAs themselves emerge as strong influences on the roles of MAs. MAs are perceived as requiring a range of skills, as being involved in a broad set of activities, and as playing an important role in information provision and analysis. The consequences of the roles of MAs show that interaction between MAs and OMs can lead to positive outcomes for performance, information, and for functional relationships, but a number of uncertainties and conflicts are associated with this. Collectively, these findings identify a number of challenges facing the MA in providing support to OMs. In phase two, the analysis of the control and decision support expectations of each OM, with respect to the MA linked to that OM, identifies the extent that MAs assist OMs in relation to performance impact, information provision, and their interaction. The findings link specific characteristics of MAs (e.g., routine and non-routine reports, individual traits) and antecedents (e.g., OMs‘ expectations, head office, regulation, FMs, OM‘s understanding of MAs) with the extent that MAs assist OMs in their roles. The study adds to the existing literature on the roles of MAs in a number of ways. The study provides a comprehensive picture of the antecedents, characteristics, and consequences associated with the roles of MAs. Through the management control theoretical lens, the findings indicate that more involvement of MAs with OMs may lead to more effective control in particular contexts, and highlights the extent that control reports are useful, and how they are used. A number of contingencies are identified that relate antecedents of the roles to assisting OMs in their roles. The use of the role theory lens in analysing the extent that MAs are not meeting OMs‘ expectations has helped explain contradictions in the literature, and identifies role conflicts and ambiguities for MAs that are new to the literature. The study extends the ‗business partner‘ and ‗bean counter‘ dichotomy to include two additional depictions of the roles of MAs. The research design makes a contribution in its use of qualitative enquiry, a two-phase approach, the inclusion of OMs as well as MAs, the adaption of role theory methodology, and in the analysis of qualitative data. The study is novel in its employment of three theoretical lenses. The study contributes to practice, and theory on the roles of MAs, in showing that MAs moving to the model of the business partner is one that is not straightforward, but one that has conditions, ambiguities, and conflicts associated with it.