Acinetobacter baumannii is a nosocomial pathogen that can colonise a wide range of anatomical sites. Antibiotic resistance in this species is a global health concern due to the emergence of pan-drug resistant clinical isolates. The persistence and survival of A. baumannii in nosocomial settings is aided by the presence of a type VI secretion system (T6SS). This bacterial nanomachine allows for the delivery of toxic effector proteins directly into target cells. Delivered effector proteins typically target essential bacterial structures, and therefore allow for the elimination of competitors. The T6SS consists of a membrane complex, a base plate, and a contractile needle. This needle, composed of repeating Hcp hexamers, has a tip composed of a trimer of VgrG proteins that is typically capped with a PAAR protein. The clinical isolate A. baumannii AB307-0294 delivers three toxic effectors: Tse15, Tde16 and the peptidoglycan amidase effector Tae17. These are delivered via non-covalent interactions with the cognate T6SS tip proteins VgrG15, VgrG16 and VgrG17, respectively. In this study, we showed that VgrG17 is important for A. baumannii AB307-0294 T6SS activity and use bacterial two hybrid analysis to show that the C-terminal ~50 amino acids of VgrG17 interact with the N-terminal 162 amino acids of Tae17. Alanine scanning mutagenesis of the C-terminal region of VgrG17 identified two amino acids crucial for Tae17 delivery as determined by interbacterial killing assays; the first time such specific interactions have been observed for effector delivery. Cross-linking mass spectrometry was used to further understand interactions. Such detailed understanding of the interactions required for the delivery of toxic effectors by the T6SS may allow for the future engineering of novel therapeutic effectors that can be delivered directly into target cells.