Typical dog trainers and owners are looking for the following specifications in a harness:
| Lighweight | Under 0.4 lbs. We don't want the harness to be more than 5% of the dog's weight, otherwise it will be too heavy and cause discomfort. Harnesses are recommended for puppies and dogs 8 lbs and up. |
| Soft | The more comfortable the harness is, the less resistant the dog will be to wearing it, and the easier it will be for the human to put it on for the dog. |
| Includes ring on back | For hooking leash and/or carabiner |
| Adjustable to neck | To accomodate varying neck girth to chest width ratios of different dog breeds, and to accomodate growing puppies. |
| Adjustable to chest | To accomodate varying neck girth to chest width ratios of different dog breeds, and to accomodate growing puppies. |
| Washable | Washable material in important because the harness can get soiled from mud, snow, rain. |
| Secure | Dog should not be able to slip out of harness even when exerting maximum force away from the human. |
| Easy to put on/time-efficient | Time should be spent on training and on walks, not on putting on the harness. |
Ultimately, the harness should be comfortable for the dog and easy for the human to put on. If the harness is not enjoyable to wear, causes discomfort or pain, every time the harness is put on the dog will fuss, and can be a major inconvenience to the human and cause delays in training progress.