I trim according to specific referece points found on each foot. This takes into consideration the horses conformation and natural function of the hoof.  When trimming a horse, I pay special attention to medial/lateral balance (side to side) and dorso/palmer balance (front to back).  This ensures the foot is properly aligned under the bony column of the leg and no undue stresses are placed on the tendons, joints or hoof capsule.  A great many problems can be remedied by a good trim, proper schedule and time.