  Stability and stabilization of linear port-Hamiltonian systems on
infinite-dimensional spaces are investigated. This class is general enough to
include models of beams and waves as well as transport and Schr\"odinger
equations with boundary control and observation. The analysis is based on the
frequency domain method which gives new results for second order
port-Hamiltonian systems and hybrid systems. Stabilizing controllers with
colocated input and output are designed. The obtained results are applied to
the Euler-Bernoulli beam.
