An innovative control rod system which may be applied to the French project ASTRID is presented. All the rods participate to power management and safety shut-down. Comparatively to traditional systems, the gains of this architecture in terms of safety margins (after shutdown, in case of incident during refueling operation and consequences of control rod withdrawal) are noticeable and allows reducing the overall number of control rods.A possible way of implementing control rods for automatic power regulation with a constant efficiency during cycle is also described.