How do you fix a horse that breaks to trot when asked to counter-canter?

A horse that breaks to trot when asked to counter-canter is telling you one of three things: it does not yet have the balance to maintain the counter-lead through the degree of curve being asked, it is reading the direction change as a signal to trot and re-depart, or the rider's aids are inadvertently signaling a transition rather than a maintenance of gait. The most productive response to a break in counter-canter is not to immediately re-depart on the counter-lead and try again in the same place — which often produces repeated breaks in the same location. Instead, Clinton Anderson recommends reducing the degree of curve immediately before re-establishing the counter-lead. If the horse broke through a corner, re-establish the counter-lead on a straighter line, confirm the lead is held, then very gradually introduce the corner again at a less demanding angle. If the horse is consistently breaking at a specific point — the end wall of the arena, the gate corner, a specific location — the break is likely location-specific rather than a general balance deficiency. The horse has learned that this location is where the lead changes, whether because changes were frequently asked there in the past or because the horse's herd instinct pulls toward the gate. Addressing this requires working specifically through that location many times on the counter-lead with a release, so the location is no longer associated with the change. For a horse that breaks due to inadequate collection, the long-term fix is returning to collection development — transitions, gymnastic exercises, and circle work — before the counter-canter is attempted again. There is no benefit in repeatedly asking for counter-canter that the horse cannot physically maintain; it only teaches the horse to break rather than teaching it to hold the lead.