Quote from the Official Standard (New amendments in red)

"Peculiarly heavy and constrained, appearing to walk with short, quick steps on tips of toes, hind feet not lifted high, appearing to skim ground, running with one or other shoulder rather advanced.  Soundness of movement of the utmost importance."

 Illustration of movement

Correct front movement with front legs wide apart.

Correct hind movement 

Paddling in front legs (fault)