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The NASA Airframe Structural Integrity Program is a multi-disciplinary program to develop analysis methodology, a fracture data base, and improved methods of NDE detection of disbonds and cracks. As part of this program, analysis tools to predict crack growth rates and fracture propagation in shell structures are being developed. This paper describes a finite element model of crack growth in layered structures, such as lap splice joints. The model is developed using separate two-dimensional meshes of individual layers which can overlap in space. These layers can be connected with either rivet elements or by adhesive elements. Cracks can be modeled in any layer, with automatic remeshing during crack growth. Using the model, an investigation was made of the effect of rivet interference on fatigue crack growth from a loaded rivet hole. It was found that the interference reduced the stress intensity factor range significantly, resulting in slower crack growth.