Requirements Engineering for Software and Systems

23

2Chapter

Mission Statement,

Customers, and

Stakeholders

Mission Statements

e first thing we need to do when undertaking the development of a new system,

or redesign of an old one, is to prepare a mission statement. e mission statement

acts as a focal point for all involved in the system, and it allows us to weigh the

importance of various features by asking the question “how does that functionality

serve the mission?” In agile methodologies, to be discussed later, we would say that

the mission statement plays the role of “system metaphor.”

Writing mission statements can be contentious business, and many people

resent or fear doing so because there can be a tendency to get bogged down on

minutiae. Sometimes, mission statements tend to get very long and, in fact, evolve

into a “vision” statement. A mission statement should be very short, descriptive,

compelling, and never detailed, whereas a vision statement can be long. e mis-

sion statement is the “how” and the statement is the “what.” A mission statement

is almost a slogan.

One of the most widely cited “good” mission statements is the one associated

with the Starship Enterprise from the original Star Trek series. at mission state-

ment read

To seek out new life, to boldly go where no man has gone before.

24  Requirements Engineering for Software and Systems

is statement is clear, compelling, and inspiring. And it is “useful”—fans of

this classic series will recall several episodes in which certain actions to be taken by

the starship crew were weighed against the mission statement.

To illustrate further, there is an apocryphal story of a multi-billion dollar-

company that manufactured cardboard boxes and other packaging. e mission

statement was something like

Our mission is to provide innovative, safe, and reliable packaging to the

world’s manufacturers.

At a corporate retreat the senior executives began to bog down in arguments

over new plants, corporate jets, marketing, and so on. In the back of the room, the

CEO, a direct descendent of one of the company’s founders was silently gesturing

with his hands. Finally the executives noticed the CEO’s actions, silenced, and

asked what he was doing. He said, “I am making the shape of a box—remember

what we do—we make boxes.” is reference to the mission statement brought the

other executives back on track.

So what might a mission statement for the baggage handling system look like?

How about

To automate all aspects of baggage handling from passenger origin

to destination.

For the pet store POS system, consider

To automate all aspects of customer purchase interaction and inven-

tory control.

ese are not necessarily clever, or awe inspiring mission statements, but they

do convey the essence of the system. And they might be useful downstream when

we need to calibrate the expectations of those involved in its specification. In glob-

ally distributed development in particular, the need for a system metaphor is of

paramount importance.

Encounter with a Customer?

Suppose your wife (or substitute “husband,” “friend,” “roommate,” or whoever)

asks you to go to the store to pick up the following items because she wants to make

a cake:

5 pounds flour ◾

12 large eggs ◾

5 pounds sugar ◾

1 pound butter ◾