The Mars Express mission was launched in June 2003 and has been providing great amounts of data since its arrival to Mars in Christmas 2003, covering a wide range of science objectives at all levels, from the surface and sub-surface geology, atmosphere dynamics and composition, up to the interaction with the magnetosphere and the characterization of the Martian sytem including its two moons, Phobos and Deimos. In these last 10 years, the Mars Express Science Operations Center has been responsible for the coordination of the scientific requirements and the implementation of the science plan, aiming to obtain the maximum scientific return of the mission while respecting the operational constraints. In this contribution we will show some of the operational challenges of the mission, focusing on the improvements and adaptations of the past years, not only in terms of technical and scientific requirements which have been varying with time, but also the optimization of the interfaces with all the teams involved.