His primary research interests relate to the theory and application of formal verification techniques to system designs, including hardware, protocols, and software. He has also done research in asynchronous circuit verification and synthesis, and in verification methods for hard real-time systems.

Prof. Dill has been working actively on policy issues in voting technology since 2003. He is the author of the "Resolution on Electronic Voting", which calls for a voter-verifiable audit trail on all voting equipment, and which has been endorsed by thousands of people, including many of the top computer scientists in the U.S. He has served on the California Secretary of State's Ad Hoc Task Force on Touch-Screen voting, the Citizens DRE Oversight Board of the Santa Clara County Registrar of Voters, and on the IEEE P1583 Voting Equipment Standards Committee. He has testified on electronic voting before the U.S. Senate and the Commission on Federal Election Reform, co-chaired by Jimmy Carter and James Baker III.

He is the founder of the Verified Voting Foundation and VerifiedVoting.org and is on the board of those organizations. In 2004, he received the Electronic Frontier Foundation's "Pioneer Award" for "for spearheading and nurturing the popular movement for integrity and transparency in modern elections."