The Surf-Hippo neuron simulator is a public domain package written in Lisp for Unix workstations and PCs that is used to investigate morphometrically and biophysically detailed compartmental models of single neurons and networks of neurons. Surf-Hippo allows ready construction of cells and networks using built-in functions and various anatomical file formats (NTS, Rodney Douglas, and Rocky Nevin formats, using a modified version of the anatomy file conversion program ntscable by JC Wathey; Neurolucida).