Necessary? No. Beneficial? Probably. I just joined our local chamber again after a hiatus for several years. Within the 1st week I had a breakfast meeting with the executive director who wanted to potentially partner up on some projects because he liked my background and how I presented myself at the 2 events I had attended that prior week. Great way to kick off 2015. But as with any networking - whether online or off it will only benefit you if you work at it. On a personal note - I prefer to do business whether for my business or personally with people I know, and I think many are the same. So this type of networking will definitely benefit you in many ways. While you may not get immediate work or referrals - over time people will know you and recommend you when someone needs your service! Also it will depend on the management of the chamber as well if it is a valuable asset for you. I happened to get referred to this one by someone who really admires the people in it. So if you do decide to join on, definitely get feedback. Every chamber is different and I do know there are some out there that offer no value.