Interviewing techniques are one of the
simplest, yet most effective methods of
requirements elicitation. Interviews can either be
structured around a specific set of questions, or
open-ended with the intention of gathering as
much useful information as possible. In most
cases both techniques are used in a single
interview. Structured interviews have the
advantage that all interviewees are asked the same
questions and that critical questions are not
inadvertently forgotten. In an unstructured
interview the interviewer may ask a few leading
questions but then allow the interview to develop
in a less rigid fashion. This approach may unearth
entirely new areas of discussion that had
previously been overlooked. As both methods
have their own advantages, it is often beneficial to
combine both techniques in a single interview.
Interviews are often conducted in stages, so that
responses from the first round can be used to
generate a deeper set of more focused questions
for the second round. It is often useful to target
the second round of interviews to stakeholders
with specific responsibilities or interests related to
the more targeted questions.