The Standard of any breed could be considered the "blueprint" for the dog's appearance.  

It describes the general characteristics,  coat texture and colour,  ear positioning and shape, the ideal height and weight, and the overall shape of the breed.  

Many of the characteristics are similar to other breeds, but it is the accumulation of all the specific features which distinguishes one breed from the others.

There are different Standards used by various countries,  but a Pyrenean Mountain Dog Standard would go something like this . . . .

The Pyrenean Mountain Dog is a natural guard dog and was originally employed as a protector of the shepherd and his flock.  The dog possesses great size, substance and power, giving the impression of an immensely strong, yet well-balanced dog. These qualities are accompanied by a certain elegance resulting from a combination of the attractive coat, the correct head and a general air of quiet confidence. Any sign of nervousness or unprovoked aggression is heavily penalised.

Head and Skull

The head gives an impression of strength but with no sign of coarseness and is not too heavy in proportion to the size of the dog.

The top of the skull, when viewed from front and side, shows a definite curve giving a somewhat domed effect; the breadth of the skull at its widest point is about equal to the length from occiput to stop.  When viewed from above, the head has the general form of a blunt "V", well filled-in below the eyes.  The sides of the head are nearly flat and of good depth.

There is no obvious stop and only a slight furrow so that the skull and the muzzle are joined by a gentle slope.  The muzzle is strong, of medium length and with a slight taper near its tip and the nose is absolutely black.

Eyes

The eyes are almond-shaped and dark amber-brown in colour.  The close-fitting eyelids are set somewhat obliquely and are bordered with black.  The expression is intelligent and contemplative.  Dogs which have drooping lower eyelids are penalised.

Ears

The ears are fairly small and triangular with rounded tips,  the root being level with the eyes.  Normally the ears lie flat against the head, but may be slightly raised when the dog is alert.

Mouth

There is a complete set of healthy strong even teeth, the incisors meeting in either a scissor or pincer bite. The two central lower incisors may be set a little deeper than others but this is not regarded as a serious fault.  The lips are close fitting, with the upper one extending downwards just sufficiently to cover the lower lip.  The lips are black or heavily marked with black as is the roof of the mouth.

Neck

The neck is fairly short, thick and muscular and some dewlap is permitted.

Forequarters

The shoulders are powerful and lie close to the body.  There is medium angulation between the shoulder blade and the part of the foreleg.  The forelegs are straight, heavily boned and well-muscled.

The elbows are not too close to the chest nor do they stand off too far from it, so that a good width of stance and a free-striding movement is obtained.  Pasterns show flexibility but not weakness.

Body

The chest is broad and of sufficient depth to reach just below the elbows.  The sides are slightly rounded and the rib cage extends well to the rear.  The back is of a good length, broad, muscular, straight and level.

Dogs usually have a more pronounced waist than bitches, giving a greater curve to the lower body line.

Hindquarters

The loins are broad and muscular with fairly prominent haunches.  The rump is slightly sloping and the tail set so that the topline curves smoothly into it.

The thighs have great strength and are heavily muscled, tapering gradually down to strong hocks.  The stifle and hock joints both have medium angulation as seen from the side.  The hind legs each carry strongly made double dewclaws and lack of this identifying characteristic is a very serious fault. 

The hind feet may turn out slightly, but the legs themselves when viewed from behind should be straight and pronounced cow hocks are heavily penalised.

Feet

The feet are short and compact with the toes being slightly arched and equipped with strong nails.

Gait

The gait is unhurried, and one gains the impression of a large dog propelled by powerful hindquarters moving steadily and smoothly well within its capacity, yet able to produce bursts of speed.  At slow speeds the Pyrenean tends to pace.

Tail

The tail is thick at the root and tapers gradually towards the tip, for preference, it should have a slight curl.  It is of sufficient length to reach below the hocks and the thick coating of fairly long hair forms an attractive plume.

In repose the tail is carried low with the tip turned slightly to one side, but as the dog becomes interested the tail rises and when he is fully alert it is curled high above the back in a circle.

Coat & Colour

The undercoat is profuse and composed of very fine hairs, whilst the longer outer coat is of coarser texture, thick and straight or slightly wavy, but never curly or fuzzy.

The coat is longer around the neck and shoulders, where it forms a mane, and towards the tail.  The forelegs are fringed.  The hair on the rear of the thighs is long, very dense and more woolly in texture, giving a "pantaloon" effect.

Bitches tend to be smoother-coated than dogs and usually have a less-developed mane.

The colour may be:
     a) mainly white with patches of badger, wolf gray or pale yellow
     b) white

Both colours are of equal merit and judges should show no preference for either.  The coloured markings can be on the head, the ears and the base of the tail, but a few patches on the body are permitted.  Areas of black hair, where the black goes right down to the roots, is a serious fault.

The nose and eye rims are black and the presence of liver pigment or pink is a serious fault..

Weight and Size

The height at the shoulders should be:     Dogs at least 71.1cm (28");     Bitches at least 66cm (26").

Most specimens will exceed these heights by several centimetres and great size is regarded as absolutely essential, provided correct type and character are retained.

The weight should be:
     Dogs at least 49.8kg (110lb);     Bitches at least 40.8kg (90lb).

These weights apply to specimens of minimum height and taller ones should weigh considerably more.  Weight should always be in proportion to height, giving a powerful dog of great strength.  Any sign of excess weight due to fat is penalised.

Note Male animals should have two apparently normal testicles fully descended into the scrotum.