This paper discusses several recent results by the author and collaborators, which are
united by the common goal of making nonlinear control theory more robust to imperfect information.
These results are also united by common technical tools, centering around input-to-state stability
(ISS), small-gain theorems, Lyapunov functions, and hybrid systems. The goal of this paper is
to present an overview of these results which highlights their unifying features and which is more
accessible to a general audience than the original technical articles.