Research summary: Continental reconstructions; supercontinents; paleomagnetism; characteristics of the Precambrian geomagnetic field. Implications for the long-term Earth evolution of geodynamics, tectonics, climate change, and life. Field- and laboratory-based research methods in paleomagnetism. Past and current projects in Angola, Australia, Botswana, Brazil, Canada, China, Finland, Mexico, Mongolia, Morocco, Namibia, Russia, South Africa, and the United States.