Reduced Basis Output Bounds Methods: Fast and Reliable Approximations and some Applications. After a brief example to motivate the methodology, I present an overview of the reduced basis output bounds methods. In particular, I will present (i) an algorithm for an adaptive approximation which could be constrained by accuracy or computing time and (ii) some ingredients for the application of these methods to the viscous Burgers equation and how it can be extended to the incompressible Navier Stokes equations.