I'm no expert but my experience agrees completely with Puppy's observations. Our counselor was completely out of her depth when dealing with our situation. She was a generalist, she counseled individuals, couples, adolescents, adults, alcoholics, etc etc. But in our situation she was grasping at straws. DO NOT go to a generic counselor. Go to someone who specializes in marriage counseling, including infidelity.
When we started counseling, I was so relieved to be in counseling at all that I didn't even think about qualifying the counselor. Bad mistake.
If your transmission is broken in your vintage Cadillac, you don't bring the car to Jiffy Lube. Bring it to the experts. Interview the counselor before the two of you ever sit down with the person. Don't be afraid to interview a bunch of 'em before making a decision.