The computer-based simulation of military tactics has largely involved the use of platform-dependent scripting resulting in behaviour that is limited, and difficult to debug and reuse. The Tactics Development Framework (TDF) addresses these shortcomings by providing design-level support for tactics modelling. Its integration with VBS3 is reported here. Categories and Subject Descriptors D.2.10 [Software Engineering]: Design—methodologies Keywords AOSE methodology; multiagent system; agent design models; cognitive modelling