  Thermodynamics of clusterized matter is studied in the framework of
statistical models with non-interacting cluster degrees of freedom. At variance
with the analytical Fisher model, exact Metropolis simulation results indicate
that the transition from homogeneous to clusterized matter lies along the
$\rho=\rho_0$ axis at all temperatures and the limiting point of the phase
diagram is not a critical point even if the surface energy vanishes at this
point. Sensitivity of the inferred phase diagram to the employed statistical
framework in the case of finite systems is discussed by considering the
grand-canonical and constant-pressure canonical ensembles. A Wigner-Seitz
formalism in which the fragment charge is neutralized by an uniform electron
distribution allows to build the phase diagram of neutron star matter.
