on the BIS forums, Spinor informed us about the release of the Chain Of Command : Command Engine X.

Like its predecessors in OFP, CEX is a script addon that enables players  to control multiple groups. Units are organized in hierarchical command chains allowing the representation of real life military units suchs platoons, companies or battalions.

CEX functionality can be incorporated into any mission. Mission designersave full control over the command structures and can freely assign command capabilities to the players. CEX is designed to be fully multiplayer compatible. Players can take any osition within the command structure on any side, be it commander-in-chief,
squad leader or private.

CEX commanders control their subordinate units via an intuitive graphical  interface which borrows elements found in real-time strategy games. Despite the intention to grant easy access, the underlying system is  ntended as a realistic simulation of higher-level combat in ArmA.

The addon contains several fully playable missions as well as templates or mission designers to base their own missions on.

More info & download : BIS forums