A 60-MW(electric) fast reactor concept, RAPID-A, without any control rods has been shown to achieve inherent safety and highly automated reactor operation and to provide reactivity control systems with maintenance-free and reliable performance over the plant design lifetime. RAPID-A is one of the variants of the refueling by all pins integrated design (RAPID), fast reactor concept, which enables quick and simplified refueling 2 months after reactor shutdown. In addition to the aforementioned advantages, unique challenges in reactivity control system design have been attempted in the RAPID-A concept. The design involves the following innovative reactivity control systems: lithium expansion modules for inherent reactivity feedback, lithium injection modules for inherent ultimate shutdown, and lithium release modules for automated reactor startup.