As balance or walker dogs, they must learn to be steady in harness and match their gait to the handler’s speed as it varies.  The dogs learn to halt and brace if the handler should fall and by standing still be available for the person to use the harness to pull themselves up.  This is an easy task as the dogs weigh about 150 pounds at maturity.  The dogs must also learn to turn right and left and to ease themselves through various doorways, elevators, aisles, checkout counters and restaurant tables.  They must learn to concentrate amid lively children, meat counters, squirrels and an odd mouse or two.  They should be able to relax and fall asleep almost anywhere for meetings, movies, lectures or work.