Topics of the Advanced Course in Operator Theory and Complex Analysis held in Seville in June 2004 ranged from determining the conformal type of Riemann surfaces, to concrete classical operators acting on classical spaces of analytic functions, passing through how the behaviour of the powers of the classical shift operator determines whether every function in a given space of analytic functions on the disk has non-tangential limits almost everywhere, and lattices of jointly invariant subspaces for two translations semigroup.