Title: Combining RLT and SDP for nonconvex quadratic programming Abstract: We consider relaxations for nonconvex quadratic programming based on combinations of the Reformulation-Linearization Technique (RLT) and Semidefinite Programming (SDP). For pairs of variables that are not near their upper or lower bounds, adding the semidefinite constraint provides a large reduction in the feasible region for the corresponding product variables in the RLT relaxation. We give computational results on nonconvex box-constrained and quadratically constrained problems. We also illustrate the effect of adding order constraints to RLT and SDP relaxations to improve bounds on highly symmetric problems.