Most of the time, the people you already know can point you to the person who knows what you need to know, but this isn't always the case. And so corporate directories are an essential tool in a modern organisation.
And yet those I've seen are often missing a trick.
No corporate directory I've seen includes database history (i.e. previous appointments/structure, with dates). This is particularly important in the fast changing world, when you want to find out who was working on a particular task last year.
Typically there is insufficient information on what people do (sometimes even their job title is omitted), their responsibilities and how their team relates to the other teams within the organisation.
And a good quality organogram generator wouldn't go amiss...