The dynamic effects associated with fibre breakage in single- and multiple-fibre composites were investigated using the finite element method. The goal of this work was to determine if the dynamic stresses differed significantly from the static stresses and, consequently, if dynamic effects were important in the prediction of subsequent fracture of the composite. For single-fibre composites, dynamic and static analyses were performed over a range of modulus values for epoxy matrices with a glass fibre to establish a range of the dynamic effects. The maximum dynamic stresses, spatial distribution of dynamic stresses, and corresponding times were evaluated. For multiple-fibre composites, the dynamic effects associated with single- and double-fibre breakage were investigated for a typical epoxy/glass composite and compared to the corresponding static problems.