Progress in the assessment of multifidelity techniques for ship hull form optimisation at MARIN is described. Surrogate-based optimisation is used, with response surfaces found from a combination of free-surface potential-flow and free-surface RANS computations. A substantial level of correspondence of the trends of the low and high-fidelity methods appears to be required. Applications of multifidelity stern design optimisation for a fast displacement ship and a containership are reviewed. Alternative low-fidelity formulations are considered.