Hitherto among specialists of tennis biomechanics exist the discords in the question of wrist functioning. One write about powerful weapon – wrist whip stroke in forehand (J. McLennan, Former President, UPSTA, North California). Others (John Yandell) say that wrist stroke is a myth, arisen because of impossibility to see in detail biomechanics of high speedy stroke of tennis player. Careful analyze of wrist’s biomechanics allows to find out that both arguing sides are right. Determined techniques of playing, determined grips and strokes make possible to use the wrist motion and hereunder to produce so called wrist whip strokes. However as showed analyzes exist the grips and strokes under which wrist practically doesn’t work, i.e. remains stable (blocked) during the stroke. The Article is provided with detailed illustrated material.