In this paper we review the current capabilities in use for the design and analysis of composite structures, and identify the main advantages of high fidelity simulation in the aerospace and energy domains. The common difficulties encountered in using these methodologies will be highlighted, and solutions proposed. A typical workflow for the design and analysis of a generic aerodynamic blade will be examined with a focus on the integration of the tools and the robustness and efficiency of the overall process. A typical workflow would be initiated within the geometry tool (CAD), and at some point would require the transfer of accurate geometric and composite layup information to a modelling system. The modification and refinement of the layup is then carried out in the analysis modelling tool and advanced nonlinear structural simulation is used to assess the performance of the component. This may include draping analysis to confirm that the component can be manufactured to the design specification, and a range of structural analyses to cover assembly, in-service loads, and limit load cases with damage and failure. The paper will review these simulation capabilities and consider the integration into a coherent workflow. These analyses are initially carried out on the ‘as designed' model, but it is important to assess the sensitivity of the structural response to variations in design parameters. Typically, the analysis would consider the variation in dimensions due to manufacturing and assembly tolerances, as well as variations in the composite construction (layup angle, ply thickness, etc) due to process variability. The workflow example will be used to illustrate the capabilities of analysis tools to carry out sensitivity assessments and to examine the robustness of the design including manufacturing variability.