Large-eddy simulation (LES) of turbulent premixed reacting flows in a gas turbine combustor (General Electric's lean premixed dry low-NOx LM6000) has been carried out to evaluate the potential of LES for design studies of realistic hardware. A flamelet model for the premixed flame is combined with a dynamic model for the subgrid kinetic energy to simulate the propagation of the turbulent flame in this high swirl and high Reynolds number flow. Comparison of the computed results with experimental data indicate good agreement in spite of relatively coarse grid resolution employed in the LES. These results provide significant confidence that LES capability for design studies of practical interest is feasible in the near future.