A "People finder" or "Yellow Pages" is one of the key supporting tools in knowledge management, but at the moment many organisations are using the wrong model when it comes to creating or buying such systems.
They are using Facbook as a model, rather than Match.com or Udate.
Let me explain.
Given that much of an organization's knowledge is tacit, and not written down, then you need to be able to find people with specific knowledge in order to be able to ask them questions, and to tap into what they know. Many organisations really do not know "who knows what", and tacit knowledge often cannot be searched for.
A dedicated tool such as a people finder or yellow pages allows just this possibility. The idea is that you should be able to type in a query such as "who knows about marketing pet food in Southeast Asia," and receive a list of people who you can talk to for advice.
Many companies that I have spoken to realise the value of a people finder, but seem instinctively to go to analogs of Facebook in order to create the sort of functionality. They look for software such as SharePoint MySite where people can create a personal page, which is then available and searchable by others. Or maybe they look at LinkedIn is an analog; again somewhere where you can create a personal CV, and maybe build some groups and some discussions threads around this.
However both Facebook and Linkedin are pretty poor at finding people based on their knowledge. They are promotional sites ; they are not sites aimed at findability, or locating people based on a set of criteria. I tried recently to find a Knowledge Manager based in Sweden via LinkedIn, and was surprised at the poor search results. I'm sure those people are out there, Linkedin could not find them (Later note, this now seems to work better).
However there is a whole class of Software Systems which are 100% designed for finding people against a set of criteria; and these are the online dating sites.
Why dating sites are a good model for people-finders
Everybody who has used an online dating site (and that is nearly half the adult single population, at least in the USA) knows that this is a very different experience to Facebook. Instead of a free form text-entry input page, where you can enter things like your taste in music or favourite band, an online dating site requires you to choose your criteria from pull down menus. Age, height, build, hair colour, eye colour, location, smoker or non smoker, preference for music types, preference for leisure activities, preferred restaurant type; all of these are chosen from a pre-set list of categories.
This taxonomic structure means you know what criteria to search for. If you are looking for someone who likes folk music, for example, then you search for "folk music" under "favourite music". You know that your potential folk-music-loving new friend will have chosen that option, rather than saying that they like folk-blues or folk-jazz, or Fairport Convention, or Mumford and Sons.
Using these preset lists is constraining in terms of data entry, but it massively enhances findability, and findability is what online dating is all about; finding the right person
The best yellow pages or people finders I have seen have used the same online dating model. They require you to select criteria from a whole set of preset lists, including knowledge topics, levels of expertise, office locations, job title, and so on. Finding a knowledge manager in Sweden is as simple as selecting "knowledge management" from the list of knowledge topics, and "Sweden" from the list of countries, because you know that Swedish knowledge manager will have chosen those same criteria from those same lists. Using these preset lists is constraining in terms of data entry, but it massively enhances findability, and findability is what a People Finder is all about; finding the person with the right knowledge.
So when you are considering an in-house People Finder system, base it on the systems that work.
Base it on the online dating sites