In choosing Best in Show at the National Dog Show presented by Purina, the dogs are examined and placed according to how closely each dog compares with the judge’s mental image of the perfect dog as described in the breed’s official standard. As part of MSNBC.com’s coverage of this competition, below is a look at the making of a champion from David Frei, analyst on NBC’s telecast of The National Dog Show.

Much of the fun of watching a dog show, either on television or in person, is that we can all be judges.

In the sport, we call it judging from outside the ring.

Everyone can have a favorite for whatever reason they choose: it can be based on technical knowledge of a breed or knowledge of dogs in general, or it can just be because you think a dog is cute.

But in the ring, it’s not quite that simple for the judge.

Dog show judges have spent years and years studying different breeds in order to become licensed to judge.

The basic purpose of the dog shows is to evaluate breeding stock to find the best dogs to produce the next generations.

To do that, judges must understand form and function: what specific job a breed was developed to perform, and what physical traits and structure will best accommodate that job.

They also need to understand dogs in general, of course, their basic anatomy and conditioning.

The ideal specimen of every breed is described in its "Breed Standard", a written description detailing the ideal specimen of that breed.

Judges must know the standard of every breed they are judging.

The standard generally relates form to function, describing general appearance, movement, temperament, and specific physical traits such as height and weight, coat, colors, eye color and shape, ear shape and placement, feet, tail, and more.

Some standards can be very specific, while some others can be rather general and leave much room for individual interpretation by judges.

This results in the sport’s subjective basis: one judge, applying his or her interpretation of the standard, giving his or her opinion of the best dog on that particular day.

If your opinion from outside the ring is different from the official judge inside the ring, just remember that judge gets and up close and personal perspective.

The judge gets to examine those traits, look in the mouth, feel the structure and conditioning that is under all that hair.

The judge also gets to watch the dogs move from the best vantage point -- in the ring.

Because of their training and experience, the judges know exactly what to look for.

Then they put all those observations together and determine which of the dogs in the ring that day best resembles that ideal specimen described in the standards.

Have fun seeing how your choices compare to those of the judges.

MORE FROM DOG SHOW

Dog daze at Westminster

Dog daze at Westminster Uno an instant hit on whirlwind press tour Uno pulls off the double, wows judges, fans Uno first beagle to be named best in show   Video: See Uno picked as best in show   Video: ‘It’s an honor’ for best in show Previous winners — where are they now?   Add Dog Show headlines to your news reader: