We are staying in Arequipa in late September 2013. Are there any recommended operators for a tour company that offers good overnight trips to the Canyon? Do you recommend that we arrange a trip through our hotel before we arrive or once we are there?
Thanks.

I am assuming you mean an overnight trip where you stay at the rim of the canyon and see the condors?

I used Giardino, they are a good mid-range operator based in Arequipa. They use a private van rather than the pool bus that is used by most inexpensive agencies. However they typically use their own hotel in Corporaque, a small village on the far side of the valley. This means you are captive for their dinner. Breakfast (good) is included. You have to get up an extra hour early for condor viewing because of their location.

If you want them, I would at least correspond prior to the trip. Although September is not the busiest month.

If you mean hiking down into the canyon, eg from Cabanaconde, that is a different story and I don't have a recommended operator. I can warn you that hiking back out is extremely tough (harder than the Inca Trail I've been told) and the guides are not as good as IT.

Thank you for the advice. We are talking about an overnight.

If you are on a budget you can walk up and down Jerusalen Street and get a package deal.

If you have a bit more money, there are hotels in Chivay and Yanque (a smaller village near by) that can also set up tours through their hotels with either shared or private transport.

Killawasi Lodge I spent an extra night there, liked it. Just went on a free hike that they offered, did not book a package thru them. I'm sure you can find lots of reviews on Trip Advisor.

http://www.killawasilodge.com/eng/

I appreciate the advice on asking the hotel. Our hotel in Arequipa recommended a private tour with Responsible Travel Peru. Does anyone have experience with this group? The price seems pretty reasonable and they are suggesting the Killawasi lodge.