One of the fundamental problems in control theory is that of controllability, the question of whether one can drive the system from one point to another with a given class of controls. A classic result in control theory of finite-dimensional systems is Rashevsky-Chow's theorem that gives a sufficient condition for controllability on any connected manifold of finite dimension. This result was proved independently and almost simultaneously by Rashevsky (1938) and Chow (1939). In this seminar, following the unified approach of A. Kriegl and P.W. Michor (1997) for a treatment of global analysis on a class of locally convex spaces known as convenient, we give a generalization of Rashevsky-Chow's theorem for control systems in regular connected manifolds modeled on convenient (infinite-dimensional) locally convex spaces which are not necessarily normable. This is a joint work with Irina Markina.