  The analysis of the age distributions of star cluster samples of different
galaxies has resulted in two very different empirical models for the
dissolution of star clusters: the Baltimore model and the Utrecht model. I
describe these two models and their differences. The Baltimore model implies
that the dissolution of star clusters is mass independent and that about 90% of
the clusters are destroyed each age dex, up to an age of about a Gyr, after
which point mass-dependent dissolution from two-body relaxation becomes the
dominant mechanism. In the Utrecht model, cluster dissolution occurs in three
stages: (i) mass-independent infant mortality due to the expulsion of gas up to
about 10 Myr; (ii) a phase of slow dynamical evolution with strong evolutionary
fading of the clusters lasting up to about a Gyr; and (iii) a phase dominated
by mass dependent-dissolution, as predicted by dynamical models. I describe the
cluster age distributions for mass-limited and magnitude-limited cluster
samples for both models. I refrain from judging the correctness of these
models.
