Enterprise Resource Planning (ERP) systems implementation is typically viewed as a customization or an integration effort to fit an organization’s business processes or existing systems. However, ERP systems implementation may also be considered as a lifecycle from inception to completion, which is likely to benefit from the use of formal systems development methodologies, including traditional methodologies (e.g. Systems Development Life Cycle, and Object Oriented Analysis and Design) and modern methodologies (e.g. Extreme Programming, and SCRUM). This research examines the use of systems development methodologies in ERP implementations and the extent to which such methodologies aid the successful implementation of ERP systems. The findings are based on reports by multiple project teams adopting different methodologies in implementing Microsoft Dynamics –GP -based ERP systems for real-world organizations.