Acinetobacter baumannii is a nosocomial pathogen that causes a range of infections, the most clinically important of which are ventilator-associated pneumonia and bloodstream infections. Antibiotic resistance in this species is a global health concern, with many recent clinical isolates being multi- or pan-drug resistant. Furthermore, A. baumannii is often able to withstand hospital cleaning and disinfecting procedures, as well as outcompete other bacteria in its environment. One mechanism that may allow A. baumannii to dominate other species in the environment and in polymicrobial infections is the type VI secretion system (T6SS), a bacterial nanomachine that allows for the delivery of toxic effector proteins directly into target cells. Delivered effector proteins target essential bacterial structures, and therefore allow for the elimination of competitors. The clinical isolate A. baumannii AB307-0294 delivers three such toxic effectors: Tse15, Tde16 and Tae17. These are delivered by the cognate T6SS tip proteins VgrG15, VgrG16 and VgrG17, respectively. While the general structure of the T6SS is relatively well characterized, little is known about the specific interactions that determine how the T6SS delivers specific effector proteins. In preliminary work, we were able to identify a 34 amino acid region of VgrG17 and a 162 amino acid region of Tae17 which were directly involved in protein-protein interactions. Furthermore, the C-terminal 16 amino acids, but not the C-terminal 27 amino acids, of VgrG17 were found dispensable for T6SS-mediated Tae17 delivery. Together these data strongly indicate that specific regions at the C-terminus of VgrG17 and the N-terminus of Tae17 are involved in interactions and the delivery of Tae17 by the T6SS in A. baumannii AB307-0294. Our aim is to identify the precise regions in VgrG17 and Tae17 that are required for the T6SS-mediated delivery of the effector. A detailed understanding of the interactions required for the delivery of toxic effectors by the T6SS will allow in the future to engineer novel effectors and deliver them directly into cells of interest.