2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49612Helicity amplitudes calculations with the program PHACT are explained. Some examples of their application in WPHACT and SIXPHACT MC's are given.7 pages, 2 figs. Talk given at QFTHEP'99 Workshop Moscow, Russia, May 27 - June 2 1999. To be published in the proceedingsHigh Energy Physics - Phenomenologytext