Let A be a function algebra on
its maximal ideal space M(A), and let P be a Gleason part of M(A). It is easily
seen that P is then a σ-compact completely regular space. We prove the
converse: if K is completely regular and σ-compact, then there exists a function
algebra whose maximal ideal space contains a part homeomorphic to K. Every
bounded continuous function on that part is the restriction of a function in
the given algebra. Consequently no subset of the part can have an analytic
structure.