This paper is a review of propagating faults in printed circuit boards (PCBs) from the perspective of using the resulting burn and melted copper patterns to identify likely locations of fault initiation. Visual examination and x-ray imaging are the main techniques for examining PCB propagating faults. Once the likely fault initiation location has been identified, fault tree analysis can be used to determine the root cause for fault initiation. The paper discusses the mechanisms by which PCB propagating faults occur. The method of determining the likely area of initiation of the fault using visual examination of the PCB burn pattern, x-ray imaging, and the layout artwork for the PCB is discussed. The paper then goes on to discuss possible root-causes for the initiation of PCB propagating faults and some of their considerations.