On matching principles.- Singular perturbations of spectra.- Feed-back control of singularly perturbed heating problems.- Singular perturbation methods in a one-dimensional free boundary problem.- Bifurcation analysis of a non linear free boundary problem from plasma physics.- Asymptotic approximations in magneto-hydrcdynamic singular perturbation problems.- Boundary layers in large scale ocean circulation.- Asymptotic methods for the Volterra-Lotka equations.- Small random perturbations of dynamical systems with applications in population genetics.- The description of jumps between Kepler orbits by boundary layer methods.- The 1:2:1-resonance, its periodic orbits and integrals.- Approximations of higher order resonances with an application to Contopoulos' model problem.- On the asymptotic validity of perturbation methods for hyperbolic differential equations.