When a function is expanded asfor some set of basis functions φ j (x), its spectral coefficients a n generally have an asymptotic approximation, as n → ∞, in the form of an inverse power series plus terms that decrease exponentially with n. If f (x) is analytic on the expansion interval, then all the coefficients of the inverse power series are zero and the problem becomes one of "beyond-all-orders" or "exponential" asymptotics. The method of steepest descent for integrals and other complexpath integration techniques can successfully connect the exponentially small behavior of the spectral coefficients to the singularities of f (x) off the expansion interval. Many examples are given in both one and two dimensions.