Abstract: The present disclosure is directed toward a target detector, a method of detecting a change in a target, target monitoring apparatus, and a method of monitoring a target. For example, a target detector includes a structure having a gain medium comprising a plurality of disordered nanostructure features and a target-sensitive material. In addition, for instance, the structure, when pumped, supports random lasing and exhibits a change in the gain of the gain medium and the random lasing in response to a change in the target. Accordingly, it is possible to use an appropriately fabricated random laser material as a detector or sensor for a target. In particular, example embodiments perform sensing operations by utilizing the properties of random lasing. That target may, for example, comprise a change in a physical parameter of an environment adjacent, surrounding or permeating the random laser material.