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Policy gradient (PG) methods and their variants lie at the heart of modern reinforcement learning. Due to the intrinsic non-concavity of value maximization, however, the theoretical underpinnings of PG-type methods have been limited even until recently. In this talk, we discuss both the ineffectiveness and effectiveness of nonconvex policy optimization. On the one hand, we demonstrate that the popular softmax policy gradient method can take exponential time to converge. On the other hand, we show that employing natural policy gradients and enforcing entropy regularization allows for fast global convergence.