A composite polygon is composed of a lattice polygon in the square lattice,
which contains in its interior an internal structure, which may also be a
lattice polygon, or a lattice tree or a lattice animal, or a lattice disc (
or a collection of these). The properties of composite polygons are conside
red in this manuscript. In particular, I shall consider the growth constant
s and generating functions of these models, as well as the statistical mech
anics of interacting models of composite polygons. It is shown that there i
s an adsorption transition of the internal structure on the containing poly
gon, and a transition which corresponds to the inflation of the containing
polygon (by the internal structure).