ESDU 82025 is the first of a group providing the designer with guidance on the methods currently available of assessing the likelihood of fracture in fibre reinforced laminates. The more complex behaviour of such composites, when compared to usual metallic materials, requires an appreciation of the modes in which failure may occur before quantitative strength assessments can be made. ESDU 82025 provides guidance on these modes for laminates comprised of continuous fibre reinforced layers. It deals first with the failure modes for individual layers in the laminate under simple loading and then relates these to the behaviour of multidirectional (layer) laminates under simple and complex loading. The modes are presented in a clear tabular form supported by notes, examples and illustrations. The data represent an essential background to the proper use of other parts of this group which give guidance on the failure criteria available, their use, and the effects of environmental and other practical considerations on strength assessment.