Tarrance served as a member of the Board of Directors of The Gallup Organization (1987–1992), and first Managing Director and President of Gallup China in Beijing (1993–1995), and as a President and Founder of Tarrance & Associates, a Houston-based national survey research company (1977–1992). Tarrance & Associates conducted hundreds of public opinion studies for national corporations, foundations, elected leaders of the U.S. Senate, U.S. House of Representatives and state governments. His acknowledged professional pursuits have included a research model built on split ticket voting, a systems approach to populist-conservatism, and studies of emerging Hispanic and internet voters.