ECCO is a Monte Carlo event generator for soft multiparticle Productio
n in high energy hadron-hadron collisions. It describes the geometrica
l aspects of a hadron with eikonal formalism and implements the dynami
cal aspects with self-similar branching of clusters. Following a brief
review of the physics underlying ECCO, a detailed description of the
program is presented. A sample main program and the output are given a
t the end.