An occupancy sensor may include a plurality of user-selectable mounting features that enable the sensor to be mounted to building structure in a variety of ways. The sensor may include: a nipple for engaging a connector associated with the building structure; one or more key hole slots for engaging fasteners associated with the building structure; and one or more flat side surfaces for engaging corresponding flat surfaces of a mounting plate associated with the building structure. A spring on the flat side surface may lock the sensor to the mounting plate. The nipple may be removable to allow the sensor to be flush mounted to the building structure. The sensor may also include a user-adjustable lens that enables a user to make discrete adjustments of the field of view of the sensor according to present levels. Other embodiments are disclosed and claimed.