High precision positioning devices based on flexural hinges are often used in 3 rd generation synchrotron radiation beamlines. In this work is presented a first approach towards the optimisation of the geometry of the notches. The obtained results indicate that the optimal shape will depend on a trade-off between the possibility to increase the compliance (i.e. decrease the stress) of the notch for a given deflection on one hand and the entity of the parasitic shift accompanying the main degree of freedom of the notch on the other. The optimum will thus be chosen from the here presented guidelines based on the application the designer is confronted with.