Dr. Dao joined the Economics Department in the College of Sciences at Eastern Illinois University in 1987 immediately after he received his Ph.D. from the University of Illinois. He taught as an instructor at Hastings College from 1980 to 1983. He received his bachelor's degree in French and Economics in 1978 and his master's degree in Economics in 1980 from Oklahoma State University. He earned a Faculty Excellence Award in the area of research/creative activity in Spring of 1996 and an Achievement and Contribution Award in research in 2009, 2011, 2013, and 2017. He was listed in Who's Who Among America's Teachers in Spring of 1998. He was a Teacher-Scholar in the College of Sciences in 1999 and in 2000.  He received a Professional Advancement Increase in 2000, 2005, 2010, and 2015. He was selected as the 2012 College of Sciences Lawrence A. Ringenberg Award recipient in recognition of his excellence in the academic community. The award is given to tenured faculty members for exceptional performance during their academic career at Eastern Illinois University. He has been visiting professor in the department of Economics at the University of Illinois since Summer of 2000, teaching Intermediate Macroeconomics, Intermediate Microeconomics, and Economic Development. He was visiting professor at Carleton University in Ottawa, Ontario, Canada during 2006-07.