General mathematical programming problems may contain redundant and nonbinding constraints. These are constraints, which can be removed from the problem without altering the feasible region or the optimal solution respectivily. Here we consider some more theoretical definitions and give reasons for selecting a special one. The emphasis is put on linear programming, but most of the material can be applied to any mathematical programming problem with linear constraints. To identify redundant constraints several methods have been proposed. We give a survey and show that all these methods are variants of a general method (Telgen (1977a)). No method is known to identify non-binding constraints directly; therefore we give some indirect ways to identify non-binding constraints. Finally, some remarks are made concerning the importance of the methods to identify redundant and nonbinding constraints in practical linear programming problems, both from a managerial and from a computational point of view.