We consider the micellization of block copolymers in solution, employing self-consistent field theory with an additional constraint that permits the examination of intermediate structures. From the information for an isolated micelle (structure, binding energy, free energy) we describe how the global thermodynamics of these systems can be obtained, which can be used to build a realistic phase diagram; the role of translational entropy must be addressed in this regard. (C) 2003 American Institute of Physics.