One of the first scholars to call attention to the importance of religion in contemporary political behavior, Wald has examined the role of churches as institutions that form political ideas, the significance of religious differences in voting, and the behavior of religious activists in public office. Together with UF colleagues, he has pioneered the study of value-based urban conflicts over school-based health centers and gay rights ordinances. Most recently, he has investigated how the political outlooks of religious groups differ across national borders. 

He helped found the Religion and Politics Section of the American Political Science Association. His widely cited text, Religion and Politics in the United States, is now undergoing revision for a fourth edition and has been published in Chinese and Indian editions. He also served on the editorial board of the Encyclopedia of Politics and Religion, and he has twice assisted the American National Election Study, the largest NSF grantee in political science, in developing better ways of measuring religious attitudes and behavior. Wald has received Fulbright fellowships on two occasions and serves on the screening committee for the Fulbright program in Israel.