Head and skull: head strongly made and large, not out of proportion to the dog's size, the muscles showing extraordinary development, more especially the maxillary. Skull broad between the ears, getting gradually less towards the eye and measuring about the same from the inner corner of the eye to back of skull as it does from ear to ear. The forehead well domed. The head is covered with very soft silky hair which should not be confined to a mere top-knot and the lighter in colour and silkier it is the better. The cheeks, starting from the ears proportionately with the skull, have a gradual taper towards the muzzle, which is deep and strongly made, and measures about 7.6 cm (3 in) in length, or in proportion to skull as tee is to five. The muzzle is covered with hair of a little darker shade than top-knot and of the same texture as the feather of the forelegs. The top of the muzzle is generally bare for about 2.5 cm (1 in) from the back part of the nose, the bareness coming to a point towards the eye, and being about 2.5 cm (1 in) broad at the nose. The nose black. Eyes: set wide apart, large, full, round but not protruding, bright, expressive of great determination, intelligence and dignity, set low and prominent in front of the head. Colour a rich dark hazel. Ears: pendulous, set well back, wide apart and low on the skull, hanging close to the cheek, with a very slight projection at the base, broad at the junction of the head and tapering almost to a point, the fore part of the ear coming almost straight down from its junction with the head to the tip. They shall harmonise in colour with the body colour. In the case of a pepper dog they are covered with a soft, straight, dark hair (in some cases almost black). In the case of a mustard dog, the hair should be mustard in colour, a shade darker than the body, but not black. All should have a thin feather of light hair starting about 5 cm (2 in) from the tip and of nearly the same colour and texture as the top-knot, which gives the ear the appearance of a distinct point. The animal is often one or two years old before the feather is shown. The cartilage and skin of the ear should not be thick, but very thin. Length of ear from 7.6 to 10.1 cm (3 to 4 in). Mouth: the inside of the mouth should be black or dark coloured. The teeth very strong, especially the canine, which are of extraordinary size for such a small dog. The canines fit well into each other, so as to give the greatest available holding and punishing power. The teeth are level in front, the upper ones very slightly overlapping the under ones. Undershot or overshot mouths are equally objectionable.
Neck: very muscular, well developed and strong, showing great power of resistance, being well set into the shoulders. Body: long, strong and flexible; ribs well sprung and round. Chest: well developed and let well down between the forelegs. Back: rather low at the shoulders having a slight downward curve and a corresponding arch over the loins, with a very slight gradual drop from top of loin to root of tail; both sides of backbone well supplied with muscles.
Forelegs: short, with immense muscular development and bone, set wide apart and chest coming well down between them. Bandy legs: objectionable. Hind legs: a little longer than the fore ones, and are set rather wide apart, but not spread out in an unnatural manner; the thighs are well developed and the hair of the same colour and texture as the fore ones but having no feather or dew claws. Feet: flat feet are objectionable. The whole claws should be dark, but the claws of all vary in shade according to the colour of the dog's body. The feet of a pepper dog should be tan, varying according to the body colour from a rich tan to a pale fawn; of a mustard dog they are a darker shade than its head. Hind feet should be much smaller than the fore feet.
Rather short, say from 20.3 to 25.4 cm , and covered on the upper side with wiry hair of a darker colour than that of the body, the hair on the under side being lighter in colour and not so wiry, with a nice feather about 5 cm long, getting shorter as it nears the tip; rather thick at the root, getting thicker for about 10.1 cm, then tapering off to a point It should not be twisted or curled in any way, but should come up with a curve like a scimitar, the, tip when excited, being in a perpendicular line with the root of the tail. It should neither be set too high nor too low. When not excited it is carried gaily and a little above the level of the body.
Coat: this is a very important point. The hair should be about 5 cm long; that from the skull to root of tail a mixture of hardish and soft hair, which gives a sort of crisp feel to the hand. The hard should not be wiry; the coat is what is termed pily or pencilled. The hair on the under part of the body is lighter in colour and softer than that on the top. The skin on the belly accords with the colour of the dog. Colour: the colour is pepper or mustard. The pepper ranges from a dark bluish-black to a light silvery-grey, the intermediate shades being preferred, the body colour coming well down the shoulder and hips, gradually merging into the leg colour. The mustards vary from a reddish-brown to a pale fawn, the head being a creamy-white, the legs and feet of a shade darker than the head. The claws are dark as in other colours. (Nearly all Dandie Dinmont Terriers have some white on the chest and some have white claws). White feet are objectionable.
Strong straight impulsion from rear giving a fluent free and easy stride reaching forward at the front. A stiff, stilted hopping or weaving gait are faults to be penalised.
Weight — 8-11 kg.