A leash has a first end for gripping and a second end for securing to an animal, a length of elastic material, and a length of inelastic material including first and second portions. The length of elastic material and length of inelastic material are configured so that application of tensile force to the first or second end of the leash extends the length of elastic material. Extension of the length of elastic material causes the first portion of the length of inelastic material to lengthen and the second portion of the length of inelastic material to correspondingly shorten. Contraction of the length of elastic material causes the second portion of the length of inelastic material to lengthen and the first portion of the inelastic material to correspondingly shorten, preventing slack in the leash upon sudden deapplication of a tensile force.
