CoJACK™ is cognitive architecture used for modelling the variation in human behaviour. It is used in simulation systems to underpin virtual actors.

CoJACK models the structural properties of the human cognitive system. As such, it constrains the models that can be implemented therein by only allowing the definition of models that fit within its structural boundaries. This provides a significant advantage over ad-hoc approaches to modelling human behaviour: as a theory of cognition, CoJACK provides a principled and testable framework for implementing realistic virtual actors.

CoJACK has been integrated with VBS2, and is described in a BRIMS 2009 paper.