Snap-fits are ubiquitous engineering features used to quickly and inexpensively assemble plastic parts. The geometric, material, and contact nonlinearities associated with snap-fit problems can present modeling challenges. Quasi-static solutions with explicit solvers are commonly used to analyze snapfits; however, OptiStruct’s nonlinear solver now possess the ability to solve these highly nonlinear problems implicitly. The first part of this study discusses an effective approach to using OptiStruct for the implicit finite element analysis of snap-fits. Once an accurate simulation model has been created, engineers typically make design changes in order to achieve desired insertion and retention forces. The second part of this study details how HyperMesh morphing and HyperStudy can be used to optimize the snap-fit design, resulting in desired insertion and retention forces while minimizing mass and ensuring structural integrity. The approach documented in this report can reduce the design time, material use, and failure rate of snap-fits used in industry.