Complexity and Good Spaces M. Intermont (Kalamazoo College) and J. Strom (Western Michigan University) intermon@kzoo.edu jeffrey.strom@wmich.edu This paper is an exploration of two ideas in the study of closed classes: the A-complexity of a space X and the notion of good spaces (spaces A for which C(A) = \overline{C(A)}). A variety of formulae for the computation of complexity are given, along with some calculations. Good spaces are characterized in terms of the functors CW_A and P_A. The main result is a countable upper bound for the complexity with respect to the suspension of A when A is a good space.