Title: Spectral Properties of a Class of Non-Local Operators by Stochastic Methods Abstract: Fractional Schr?dinger and jump-diffusion operators provide useful tools in modelling relativistic quantum and anomalous kinetic phenomena. Driven by such applications I will formulate some problems involving spectral and analytic properties of evolution semigroups generated by Bernstein functions of the Laplacian, including these operators as special cases. By using a combination of functional integration, potential theory and Wiener-Hopf methods, I will present results on asymptotic properties of the spectrum and eigenfunctions of the non-local operators involved.