The control and co-ordination of groups of agents in battlefield simulations is difficult. Some of the important issues include the production of plans, the assignment of agents to roles and the monitoring of plan execution. A framework, based on theories from multi-agent systems, has been implemented to support co-ordinated group behaviours. This has been used for plan execution, monitoring and repair. Current work is focused on mixedinitiative planning, making use of existing terrain-based planners.