If you usually walk your dog on a leash, a harness is a good alternative to a collar. The harness is particularly comfortable for jogging, for use with training or retractable leashes, and if your dog has health problems (e.g. respiratory problems).
After measuring the chest circumference, the harness must be adjusted according to the following rules:
the dog must be able to move its shoulders and front legs freely
the abdominal strap must be positioned on the true ribs of the rib cage (measure a space of 2-3 fingers between the armpit and the abdominal strap, more for larger sizes)
the chest strap must be positioned along the sternum
