I've been carefully doing Link building "white-hat" from some good sites for over a year now, and so far it's been successful.
Along the way, I've had a few opportunities for acquiring links from some pretty big good sites. However, they were asking for "direct link exchange". (no A-B-C)
So I'm wondering, is it safe to do some link exchange now and then? Or are there any special ways to do it correctly?
Please advise if you have done this in the past on several occasions without any google penalizations.
Thank you for your valuable insights