The following are excerpts from the official Collie standard as adopted by the A.K.C.

General Character — The Collie is a lithe, strong, responsive, active dog, carrying no useless timber, standing naturally straight and firm. The deep, moderately wide chest shows strength, the sloping shoulders and well bent hocks indicate speed and grace, and the face shows high intelligence. The Collie presents an impressive, proud picture of true balance, each part being in harmonious proportion to every other part and to the whole. Timidity, frailness, sullenness, viciousness, lack of animation, cumbersome appearance and lack of overall balance impair the general character.

Appearance — The Collie comes in two varieties, either the rough coated or smooth coated variety. The rough coated Collie carries a long and abundant coat over it’s entire body with the exception of the head and legs. The smooth coated variety carries a short, hard, dense, flat coat of good texture. Both varieties are double coated, with an undercoat that is soft, furry, and so close together that it is difficult to see the  skin when the hair is parted.