I know this is an old thread, but I wanted to add my $.02 about whether relief is less sculptural than sculpture in the round. Coming from a traditional viewpoint, I think it's a ridiculous statement. I would say, yes, that doing abstract pieces might be less interesting in relief because you have less space to work within, but figurative relief is just as rich a subject area as sculpture in the round. It's not easy to learn to juxtapose planes so that they read well and it's not as simple as flattening everything out. A painter would not be able to jump right in and do a relief unless he/she had some latent sculptural talent because it is not at all like painting. Certain types of foreshortening are next to impossible to pull off. The constraints of positioning and the "frame" just mean it requires more creativity to solve these types of problems; relief is in no way a lesser art form. Here is one of my pieces, just for fun. This is all below the surface of the background, which is not usually how I work and the first time I had done this type. Different lighting changes the effect, which I find interesting and challenging as well because I like to have it look nice in as many lighting situations as possible.