Conservation framing means using acid free materials and doing nothing to harm or change the item being framed. For instance, we don't use masking tape to hinge prints or photos. We use acid free framer's tape that can be removed when necessary. We don't glue down anything that would be harmed by removing the glue; instead we sew it. (That's Vicky's job--Hugh doesn't sew.)
Conservation framing also means using conservation glass which blocks out 98% of UV rays and keeps your photos and prints from fading. Anything on paper will fade unless kept in total darkness. Just because you don't hang it in the sunlight doesn't mean it won't fade. Using conservation glass will extend the life of your artwork many, many times. And it isn't that expensive!.