Requirements and design

Key concepts
 
Client requirements are a notorious problem in many fields. There's a widespread view that the problem is due to clients not making their mind up, or being disorganised. The real reasons run deeper; fortunately, there are effective methods for fixing the problem, which are not as widely known as they should be.
 
Why requirements are difficult, in one diagram
Why clients change their minds, and what you can do about it
Requirements that clients don't talk about
Are client requirements infinite and unknowable?
Why clients can't know what they don't know
 
Solutions
 
The articles below describe ways of clarifying client requirements within a systematic overall process.
 
Identifying and clarifying client requirements
More on identifying and clarifying client requirements
How not to handle client requirements
More examples of how not to handle client requirements
How to tell if you've met a client's goals
Why clients change their minds, and how to fix the problem
Finding constraints and boundaries in requirements
Requirements that clients don't talk about
 
Methods
 
The articles below describe methods that are useful for identifying requirements rigorously and systematically, with particular reference to requirements that clients are likely to miss.
 

 

When design meets requirements


 
Requirements overlap considerably with design. The articles below discuss this overlap, with particular reference to the usability of designs.
 

 
Regularities in requirements
 
There are regularities and trends in requirements across projects and across time. The articles below discuss this issue.