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ChaPter 2 • underStanding and modeling organizational SyStemS 39

Figure 2.18
• Use cases effectively communicate systems requirements because the diagrams are
kept simple. The main reasons for writing use
• Use cases allow people to tell stories. cases are their effectiveness in
• Use case stories make sense to nontechnical people. communicating with users and
• Use cases do not depend on a special language. their capturing of user stories.
• Use cases can describe most functional requirements (such as interactions between
actors and applications).
• Use cases can describe nonfunctional requirements (such as performance and
maintainability) through the use of stereotypes.
• Use cases help analysts define boundaries.
• Use cases can be traceable, allowing analysts to identify links between use cases and
other design and documentation tools.

Why Use Case Diagrams Are Helpful
No matter what method you use to develop your system (traditional SDLC methods, agile meth-
ods, or object-oriented methods), you will find that use cases are very valuable. The use case
diagrams identify all the actors in the problem domain, and a systems analyst can concentrate on
what humans want and need to use the system, extend their capabilities, and enjoy their interac-
tion with technology. The main reasons for writing use cases are shown in Figure 2.18.
The actions that need to be completed are also clearly shown on the use case diagram. This
not only makes it easy for the analyst to identify processes, but it also aids in communication
with other analysts on the team and business executives.
The use case scenario is also worthwhile. Since a lot of the information the users impart to
the analyst already takes the form of stories, it is easy to capture the stories on a use case scenario
form. The use case scenario always documents the triggering event so that an analyst can always
trace the steps that led to other use cases. Since the steps performed are noted, it is possible to
employ use case scenarios to write logical processes.
Use case diagrams are becoming popular because of their simplicity and lack of technical
detail. They are used to show the scope of a system, along with the major features of the system
and the actors who work with those major features. The users see the system and they can react to
it and provide feedback. They may also help to determine whether to build or buy the software.

Levels of Management
Management in organizations exists on three broad, horizontal levels: operational control,
managerial planning and control (middle management), and strategic management, as shown in
Figure 2.19. Each level carries its own responsibilities, and all work toward achieving organiza-
tional goals and objectives in their own ways.

Figure 2.19
Management in organizations
exists on three horizontal levels:
operational control, managerial
Strategic planning and control, and strategic
Management management.

Managerial
Planning and Control

Operational Control