An operation is a service that an instance of a class can be requested to perform. It has a name and a list of arguments. The class supplies a method to perform the operation. Within System Architect, you specify methods that a class can perform within the Methods grid in the class definition. Methods of the class are displayed in the third compartment of a UML class symbol.

Constructors are special methods that are used in some languages (that is, C++) to create an instance of a class. Within System Architect, constructors are considered to be a special case of Method. Methods having a Name equal to their owning Class are assumed to be Constructors.