Abstract: An articulating clamp assembly for attaching a traffic control device to a mast arm upright pole or other support member. The clamp assembly includes a saddle clamp which adjustably attaches to the vertical elongate member on the bracket of a traffic signal. Either a cable clamp or a tenon clamp can be included for attaching the assembly to the mast arm or pole. The cable clamp includes inner and outer tubular members which are rotatable relative to each other, and of course the anchor plate of the cable clamp can be positioned anywhere along the length of the mast arm or pole and anywhere around the circumference. Similarly, the tubular end of the tenon clamp can rotated relative to the mast arm for proper positioning. The mast arm clamp and the saddle clamp are joined by a pair of serrated rings which permit a wide range of rotational adjustment between the two clamp members. Thus, the articulating clamp assembly of the present invention permits multiple adjustments.