my own counter for monks is usually a few units of archer cav (with a more balanced army hiding in the woods or somewhere else). My cav archers simply while away their time picking off monks; while the monks (the AI is pretty predictible) spends its energy chasing after my cav, the bulk of my army sets up somewhere advantageous. once the CA have run out of ammo (or the timer is halfway around) i recall my CA behind my new lines and let my army deal with the rest of the now-depleted monks (with line archers and remaining cav archers continuing to shower the enemy while my combat troops engage). it works pretty well against the Kaga Ronin army in the campaign, which is usually almost all-monk early in the game.

the cost of archer cav are a little less than than monks, so this isn't a one-for-one strategy for fighting monks like above, just another suggestion.

[This message has been edited by solypsist (edited 06-12-2001).]