Active-matrix liquid crystal displays (AMLCD) have come into increasing use in a variety of applications. As the size of the displays has gotten larger, their proper testing and repair has become critical. Quite simply, it is too costly to discard displays that fail to pass initial tests. Schemes have been devised that test AMLCDs as to whether they are operating or not, i.e., test that merely indicate whether the display will work, or not, once it is assembled. That is no longer enough. Manufacturers must know why a device is inoperable and whether it can be repaired. Since AMLCDs are basically large integrated circuits, a number of test and repair techniques have been borrowed from the semiconductor industry. This paper describes a method by which AMLCDs, especially large area devices, can be tested and repaired. This method primarily involves the incorporation of electrical probing to test individual lines and pixels. Once the defects have been located, lasers are used to effect the required repairs via material removal and deposition.