I, too, have been frustrated for many years at the proscription of empty algebras. However, I feel that there may be some movement in people's positions from time to time, which may continue if we all try to be diplomatic. I would add that I don't think universal algebraists are the only ones that have this particular opinion. The logicians tend to require structures to be nonempty. I believe this goes back to a decision by Tarski, although I certainly wasn't there. Given the strong allegiance some universal algebraists have to logic, I think that it would be important to try to have a dialog with the logicians about this. Thus, I was very interested in Dr. Barr's remarks concerning a better definition of ultraproducts. About _types_ and _sorts_: I think they are different. To me, a _type_ is an N-tuple of sets S_n, where elements of S_n are n-ary basic operations. There is a free functor from types to clones (or theories), and a forgetful functor the other way. However, in this situation, there would only be one _sort_. For what it's worth, I have a half-written paper that allows any category of sorts, with an additional structure of operations from limits of diagrams in the sort category (which limit might not exist!) back to objects in the sort category. I sent in an abstract about this to the UACT conference. Unfortunately, I seem to have put that project on the back burner. Bill Rowan ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++