This article demonstrates the use of response sensitivities in numerical simulation of composite processing via four different application examples: real-time result validation, model calibration, reliability analysis, and optimization. The analyses are carried out with integrated simulation software with new response sensitivity capabilities. Notably, the response sensitivities are computed by the direct differentiation method. This is an efficient and accurate alternative to the finite difference approaches. A brief review of the derivation and implementation of sensitivity equations is provided. The primary objective of this article is to demonstrate and promote a suite of techniques to incorporate uncertainties into the simulation of the composite manufacturing process, facilitated by efficient sensitivity computations.