Hybrid laminates and advanced composites represent the third generation of aerospace materials. Aircraft hybrid laminates display several desirable characteristics but are susceptible to delamination. The technical focus of this work was to simulate delamination in GLARE laminates subjected to Mode-I loading.The report aims to introduce delamination growth modelled as crack propagation through the resin rich adhesive layer.This goal was accomplished using an X-FEM crack growth model in Abacus FEA software. Mode-I loading was simulated based on DCB test according to ASTM standards. This monograph contains step by step instructions to model a typical test specimen, simulate a total delamination growth of 30 mm including post processing steps required to obtain load-displacement plots. The approach was validated by comparing the test results to experimental results and cohesive zone model data available in the literature. Unlike the CZM approach this model can be extended to simulate migration of delamination across the laminae.