There’s a lot of information on the Interweb about how to write a functional specification (FS for short, aka software requirements specification, system specification, product specification.
What I have struggled to find, though, is a good, detailed description of what should actually go in an FS and, in particular, to what level of detail. When asked this question, most BAs answer, “it depends”. Whilst this is true, I think we can improve on it by drawing some clear boundaries around how much detail is allowed, and how much is too much.
Therefore, I present a specification for a functional specification. This my own view and by no means an industry standard, but it works for me. 🙂