Having agreed on the problem or problems to be resolved with the specification, the committee now has to define what will solve the problem. For example, to use a common nursery rhyme, the Use Case is ‘getting water for Liza’ while the requirement is the transportation by Henry of fluid from point ‘a’ to point ‘b’.
Henry could use a variety of options to bring Liza the water and requirements form the basis on which Henry selected the bucket. Some Requirements in this case likely are: must be portable by a single person, sufficient (i.e. minimum and maximum) volume to per unit, able to be lowered and withdrawn from a well, and as the song tells us repairable by the User. We all know that the resulting specification is a bucket, however Henry unfortunately has a hole in that bucket – and the song goes on.
Now that the committee (in this case Henry & Liza) knows what is needed to be able to solve the problem; the next step is figuring out how to solve it – write the specification and that will be Part 3 of this series.