When it comes to two way linking; if you're talking about making lots of links to things like reciprocal link farms, or sites unrelated to yours... don't, that will only hurt you.
It is perfectly natural (and beneficial) to link out to sites related to you (and in your area of expertise). But stay away from places asking for links solely for SEO purposes.
That would be the logical thing to do, but a lot fail to realize. You have to consider what linking with other sites will cost you. If indeed you linked to sites that are not related to your field/business, they might take advantage of you and could create hassle if they bombard you with unnecessary stuff like spamming and such.
I think it's best to link to sites that are of the same field and/or interest with you for in that way, not only will you be gaining knowledge from them, but you can also build good relationship with like-minded people. After all, building from ground up would require a community. :)
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Emma Ames, Pepper Virtual Assistant, http://www.peppervirtualassistant.com/



