The substance of this memo is to initiate the naﶥ LISP user into the intricacies of the system at the Project MAC A.I. Lab. It is composed, at this time, of a Progress Report on the development of the LISP system and a few appendices but as such should be nearly adequate to start out a person who understands the basic ideas of LISP, and has understood a minimal part of the LISP 1.5 Primer.