Stacking faults and antiphase boundaries (APBs) are studied by using the CBED and LACBED techniques. Typical effects are observed on the excess and deficiency lines. For stacking faults, these lines split into a main and a subsidiary line. The relative intensity and position of these two lines allow the identification of the fault vector R. For antiphase boundaries, the lines split into two lines with equal intensity. This property is typical of APBs and can be used to identify them. The fault or antiphase plane can be identified from trace analyses performed on LACBED patterns. (C) 2003 Elsevier Science B.V. All rights reserved.