The research paper examines the incidence of sub-optimal effects in successful joint operations, in particular the command function in one successful joint operation. This study has been undertaken because research about joint operations tends to be normative and focus on the advantages and opportunities in joint operations instead of examining the problems that may arise. Previous research suggests that the command function should be centralized to achieve synergies. It is also suggested that the command function should be decentralized to enable lower command echelons to act on situations occurring in the theatre of operations. Since no existing theories explain this command-dilemma in full, a theory has been developed for the study’s analysis. Research design is that of a single-case study of the German operation Fall Gelb (Case Yellow) 1940. Empirical data has been gathered through written documents covering the selected case. Results of analysis reveal that there were sub-optimal effects in terms of inefficiencies during the operation Fall Gelb and a conclusion can be drawn that successful joint operations also have sub- optimal effects. The study contributes to existing research by providing a more nuanced understanding of joint operations with a focus on sub-optimal aspects.