Hello I created a small library to define “enums” in Common Lisp. It is Yet Another^n DEFENUM macro. The site is defenum.sourceforge.net. A blog entry with some comments (especially by Farè) is here: http://within-parens.blogspot.gr/2014/01/enumerated-types-in-cl.html I would not mind having a discussion about the beast. The design is simply “let’s do in CL what they do in Java and C/C++”, so it does have some shortcomings and the implementation is still sub-optimal. All the best -- Marco Antoniotti