A tunable polarization dependent loss element is formed of a fiber including a highly tilted optical grating. The grating is formed at an angle of approximately 45 so as to preferentially scatter one polarization state out of the fiber core while allowing the remaining, orthogonal polarization to propagate unimpeded. By twisting the ends of the fiber grating structure, the orientation of the grating with respect to the fiber optical axis will be changed, modifying the amount of optical signal existing in each polarization state. In one embodiment, both ends may be rotated in the same direction through the same angular displacement, resulting in merely rotating the principle states of polarization in the fiber. Alternatively, the ends of the grating may be rotated (twisted) in opposite directions so as to couple all of the light signal into a single polarization state, reducing the amount of polarization dependent loss to essentially zero. Therefore, by controlling the twist imparted to the grating, the amount of exhibited polarization dependent loss can also be controlled.