Sather Lisp is a primitive Lisp interpreter completely written in Sather 1.0. Currently no local function definitions are possible, and therefore no higher order functions can be defined directly (i.e., local lambda's do not work correctly). However, arbitrary long integers and rational numbers are fully supported. Sather Lisp serves as an example for a non_trivial but still comprehensible Sather 1.0 application. Its simplicity lead to a small and straightforward implementation (less than 1000 lines of code, including comments and empty lines), but the interpreter is still powerful enough to give valuable insights into the principles of list processing. It can either be used to learn Sather by studying a concrete application, or to get a glance of list processing by studying the implementation details. This documentation is only a brief description of the interpreter functionality (its user interface) and is not intended as a Lisp tutorial. The reader is referred to the standard literature for a more thourough introduction into the topic (e.g., P.H. Winston and B.K.P. Horn (1984), Lisp, 2nd edition, Addison_Wesley).