I have always been a fan of LinkedIn. For professional networking it is unsurpassed, outdone only by live events where you can shake hands, make eye contact and exchange business cards.
I am not exactly sure when this feature was added but I would love to shake the hand of the person who enhanced the "relationship" tab to allow for notes and other information about each contact that only you can see. One of these special fields is "how you met."
I attend a lot of conferences, business meetings and social events which means I collect a lot of business cards. I have always been pretty diligent about keeping this contact information in my personal address book, but often the 'connection' is made on-line in LinkedIn as well. I also connect frequently with people who I meet by phone, video-conference, through publications or even by referral.
Of all the things I have the most trouble tracking it is how and where I first met someone. Being not just able, but prompted to include this tidbit of information when adding a new connection is pure gold. Now, when looking back at people, particularly people with whom there has been little contact for a long time, one can easily be aware of the source of the connection.
By the way, the section allows you to add multiple notes about the individual such as personal information or other background material you may have, activities or communications with the person. You can set up reminders to prompt you to call, write or take some other action. The contact can also be "tagged" or assigned to a group.
By using these features, which are included in the free version of the product, you can have pretty robust contact tracking system.
Recently, I started to go back through my contacts, reconnecting with people and carefully adding notes. Not only has it been working well, but I even get a laugh when some of them can't recall where we met either.
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