Konstantin Guericke, one of the founders of LinkedIN was kind enough to give me some time and answers about the past and future of the online social giant.

Tell me where the idea from LinkedIn came from and what lead you in the direction you took.The co-founders (of which I'm one) all had over 10 years of work experience, and we all learned that relationships matter in business. That's how we got in the door with business partners, hired great employees, found investors, did due diligence, selected service providers, got inside information, etc. And, of course, most of us got jobs through relationships with former classmates, co-workers, business partners, clients, etc. However, there was no place where we could manage our business relationships and leverage them effectively to get things done. The closest was our Outlook contacts folder, but that only provided email addresses and phone numbers. It didn't allow us to search for experts by topic, select contacts by industry, show us who our contacts know, etc. And it was a pain to update this information. On top of that, we felt we were losing touch with people. When you have 10 years of work experience, there are hundreds of co-workers who you know well enough to respect their opinions and who may have a contact that can help you. So, there was a need for something like LinkedIn.

Give me an idea of the team behind LinkedIn.We are 45 employees. Most of our employees are in the product team: server engineers, desktop engineers (we have toolbars for Outlook, IE, Firefox, Mac, etc.), database engineers, product managers, Web Designers, UI designers, etc.. Having 4.6 million users (half active on the site in the past 90 days), we also have people who make sure the servers don't go down and those who make sure we reply to inquiries, especially now that more and more of our users are using our premium services. When you pay $15 to $200 a month, you expect good service.

We also have two people who just analyze the way our users are using LinkedIn to help us figure out how we can improve the site. Besides me, there is only one other marketing person, and she is in charge of over 1,000 customers who are using our LinkedIn for Groups product, which lets alumni associations, industry conferences and professional association create specific member-only groups within the overall LinkedIn Network.

Being a viral site, isn�t it stupid to limit invitations, as you recently announced you would do?

Since each connection on LinkedIn means you need to be willing to introduce your connection whenever he or she wants to reach someone you or your contacts know, we never thought people would want to have more than a few hundred connections. While our user agreement clearly spells out that you may only invite people who know you and invitees have a button to report users who invited them and who they don�t know, we learned that a small group of our users (less than 0.01% of our user base) was using the invitation mechanism to �get to know people.� They didn�t mean any harm, but we received a lot of complaints, and users asked us why we let them invite so many people in the first place. We realized we should be more pro-active, and when we looked at the data, we found that people who sent out more than 3,000 invitations were much more likely to draw complaints, and so we made that the default invitation limit. When users reach that limit and they want to send more invitations, they can request the cap to be raised, and we can then look into their track record of whether most people accepted their invitations and if there were more than a couple of people who complained about receiving invitations from this individual. This puts less of a burden on our user base to report people who violate the user agreement, and I think it will make people select more carefully whom they invite to connect. This applies to both free as well as paying members. Privacy is non-negotiable.

That makes so much sense. So many of us have received totally uninvited and unknown requests to connect and I can appreciate the thought that probably went into the answer to the problem.

Can you run down the additions you made to the site in the past year?

Two out of three of our 4.6 million members joined in the past 12 months, so chances are many of our members don�t even know what LinkedIn looked like a year ago. In the past year, we added the following:

1) The ability to re-connect with old co-workers [since this has been a very popular feature, there will be several enhancements coming to this in 2006)

2) Job listings, sorted by degrees of separation and with the ability to get referred to the hiring manager/recruiter

3) Business service provider directory (check the provider link on https://www.linkedin.com/services)

4) Ability to broadcast updates to your profile, jobs you have posted, etc. to your connections

5) Find implied connections via the reference search (https://www.linkedin.com/rs)

6) A name search that searches not just your own network, but the entire LinkedIn network (https://www.linkedin.com/ns)

7) Ability to contact users three or more degrees away directly through InMail or OpenLink, if the recipient provides access

8) Seeking out people welcoming contact through the OpenLink Network

9) Improved management of sent contact requests (introductions, InMails, OpenLink messages, group introductions, etc.)

10) Ability to your network with you when looking at job boards (https://www.linkedin.com/static?key=jobsinsider_download)

11) Plug-ins for Firefox and the Mac (for all those who are not friends of Microsoft)

12) Ability to save invitation texts and to auto-fill contact records through the Outlook toolbar (https://www.linkedin.com/static?key=outlook_toolbar_download)

13) Easy creation of a customizable, professional-looking signature file, with a link to one's signature file

14) Download your connections

15) Integration of over 4 million jobs through a partnership with SimplyHired

16) Integration with corporate software applications, like Taleo and Salesforce.com

I think 1), 5) and 7) were the big ones. 1) is a free feature, and it�s been one of our most popular features. Due to its popularity, we plan to enhance it dramatically in the next month or two. 5) and 7) are premium features that are only available to subscribers. They, too, have been very popular, and so we no longer have to raise money :)

OK, stop. Now I'm feeling lazy... That's a list of accomplisments to be proud of.

I'll have to say I've loved LinkedIN for some time, and I use it several times a week. I've made some great connections there that have led to some nice collaboration. In fact, through LinkedIN, I've hooked up with some like-minded geeks (IT guys) and PR people who are collaborating on a monthly podcast, the podcast roundtable. LinkedIN has been a great help to me.

Where do you hope LinkedIn will be in one year?

Over 1.6 million of our 4.6 million users are already in Europe and almost 500,000 are in Asia. This is pretty amazing, considering that we never marketed our products there, don�t provide support for foreign languages, etc. over a third of our revenue already comes from outside of the US, so I expect us to capitalize on this by expanding more internationally though localized versions of LinkedIn. We also have some pretty interesting ideas to further improve the LinkedIn experience for recruiters or hiring managers who are looking to recruit on LinkedIn through referrals from fellow employees or other trusted connections. There are also still a lot of things to be done to help people manage their professional relationships more effectively. While currently people turn to a general-purpose search engine like Google when they are looking up a person, I think by the end of this year, most people will turn to LinkedIn�in the business context, anyway. Increasingly, it will be expected that a professional has a LinkedIn profile, and people will have one, just so that opportunity can find them. Our job is to continue to make sure that incoming contacts are more likely or not to represent an opportunity for our users.

In five years?

Boy, that�s a tough one. LinkedIn didn�t even exist three years ago. I�m guessing that we will have over 100 million members, a pretty substantial chunk of the world�s business population. Also, access to profile and relationship information from LinkedIn will be integrated into a myriad of applications�not just Outlook, CRM systems and applicant tracking systems (which is where it is integrated now), but into news, mobile devices, etc. Forget called ID�you should see if the caller knows someone you know and get a sense of who they are before you decide whether to take the call or let it go to voice mail. When you are sitting in an airplane or listening to a boring panel discussion at a conference, LinkedIn could alert you to the fact that a former client of your current boss is sitting two seats down and is a whiz at search engine optimization. I�m sure there is a lot we can�t even imagine. There are already people who used LinkedIn with great success for their wedding!

If you haven't signed up to be a LinkedIN member, then you are really missing out. Visit LinkedIN at www.linkedin.com