Despite the fact that, for most of us, time is a central focus of our lives, the examination of what we do with our time and why has received limited attention as a method for understanding human behavior in the social sciences. Humans' view and use of time shows tremendous variation, including across cultures and with age, lifestyle, and gender. For many of us, a sense of time is ever-present. We speak of time as a commodity, a resource, an ally, an enemy, and a gift. It maybe on our side, on our hands, with us, or against us. We perceive it to change speeds (dragging vs. flying vs. standing still) and lest it get away on us, we attempt to harness and control it with clocks, schedules, and deadlines. We describe our use of time in a myriad ofways: we spend it, save it, waste it, kill it, give it, take it, and grab it. The impetus for this book grew from a three-day research symposium where established time use researchers from a variety of disciplines from Canada, the United States, Finland, Australia, and New Zealand gathered together to merge their knowledge and resources to collaborate in exam- ing the relationship between human time utilization and health and we- being. We gratefully acknowledge the financial support for the sym- sium received from the Government of Canada's Program for Inter- tional Research Linkages and M. Powell Lawton, without whose support and encouragement this book would likely not exist.