Ibarra (born September 29, 1941 in Negros Occidental, Philippines) is a Filipino-American theoretical computer scientist, prominent for work in automata theory, formal languages, design and analysis of algorithms and computational complexity theory.
He was a Professor of the Department of Computer Science at the University of California-Santa Barbara until his retirement in 2011.
Previously, he was on the faculties of UC Berkeley (1967-1969) and the University of Minnesota (1969-1990).
He is currently a Distinguished Professor Emeritus at UCSB.