The present study addresses the optimisation of the locations of the error sensors and the control actuators in an active noise and vibration control system. This system is implemented on a double panel partition in order to improve its sound insulation characteristics in the low frequency range. For this purpose, a model of the active control system is ยฎrst presented and combined with a model of the considered vibro-acoustic system. This yields an integrated simulation model of the actively controlled structure, allowing both structural and acoustical control. Afterwards, the locations of the control actuators and the error sensors are optimised in order to increase the performance of the active noise and vibration control system, deยฎned as the average reduction of the radiated sound power over the frequency band of interest. Dierent optimisation algorithms have been implemented. Besides the genetic algorithm, which is naturally well-suited for discretised problems, a number of gradient methods are also tested. Finally the performances of all methods are compared in terms of quality of the obtained solution, computation time and algorithm complexity. This comparison shows that the best gradient method converges faster and yields a better ยฎnal solution than the best genetic algorithm or than the randomly perturbed gradient method.