Purpose – The purpose of this thesis is to continue the research on Agile teams in large projects and large organizations. Specifically, this thesis seeks to understand what key success factors there are for enabling autonomous Agile teams at large-scale and how they can be prioritized. Method – This thesis is based on a case study at Saab AB, a large Swedish firm within the defense industry. In addition to the case study, interviews with representatives from three separate firms were conducted. The data consist of 13 interviewees with employees at Saab AB and three from the separate firms. A thematic analysis of the data was conducted following a six-step procedure. Results – The results show eight themes with accumulated key success factors from extant literature and empirical findings from this study. The themes are Context, Agile Approach, Other, Dependencies, Planning & Goal Setting, Management Support, Team Stability and Culture, and they are prioritized in that order. Furthermore, a diagnostic questionnaire is established as a tool for managers and teams wanting to enable autonomous Agile teams at large-scale. Theoretical Implications – This thesis contributes to current literature by combining theories of autonomous teams and Agile at large-scale, and by presenting key success factors for this combination to work. It also adds to lacking theory of autonomous team at large organizations. Practical Implications – Autonomy is a central function of Agile teams. Agile methods are becoming increasingly popular at the large-scale. Understanding the key success factors presented in the findings and reviewing the questionnaire, managers can further their enablement of autonomous Agile teams at the large-scale and understand how far they have come. Similarly, teams can understand how they can contribute.