Election integrity is the extent to which the outcome of the election matches the will of the voters. When most people think about threats to election integrity, security and fraud are the primary concerns. However, there is another equally important threat to election integrity: voting system usability. That is, does what actually gets on to the ballots accurately reflect the will of the voters? All the security in the world means very little if what is recorded on the ballots is itself inaccurate. How could that happen? It happens when the ballot itself is badly designed and that poor design leads voters into making errors. While it is unclear whether any major election in the U.S. has ever been directly compromised by hacking, it is clear that multiple such elections have been decided by poor ballot usability. Researchers at Rice University are at the forefront of academic research on voting system usability, including applying that knowledge to the design of real voting systems.