A system, tracker, program product, and methods to facilitate and verify proper target alignment for radiation delivery are provided. The system includes a radiation delivery apparatus having a radiation emitter, a rotating assembly controlled by a controller, and an application computer which provides treatment delivery instructions to the controller. The system also includes a trackable body having a trackable body reference point to be positioned adjacent a surface point of a patient to determine a position of such surface point. The system also includes an apparatus to track a trackable body which has a trackable body detector to detect a position of indicators carried by the trackable body and a trackable body determiner to determine a position of the trackable body reference point. The system also includes a target alignment analyzing computer having memory and target alignment analyzing program product stored therein to aid a user of the system to make and display various patient body-surface related measurements.