Peter A. Coming Palo Alto, CA November, 2000 This volwne represents a distillation of the plenary sessions at a unique millenniwn- year event -a World Congress of the Systems Sciences in conjunction with the 44th annual meeting of the International Society for the Systems Sciences (ISSS). The overall theme of the conference was "Understanding Complexity in the New Millenniwn. " Held at Ryerson Polytechnic University in Toronto, Canada, from July 16-22,2000, the conference included some 350 participants from over 30 countries, many of whom were representatives of the 21 organizations and...