Thomas W. Reps (born 28 May 1956, United States) is an American computer scientist known for his contributions to automatic program analysis. Dr. Reps is Professor of Computer Science in the Computer Sciences Department of the University of Wisconsin–Madison, which he joined in 1985. Reps is the author or co-author of four books and more than one hundred seventy-five papers describing his research. His work has covered a wide variety of topics, including program slicing, data-flow analysis, pointer analysis, model checking, computer security, instrumentation (computer programming), language-based program-development environments, the use of program profiling in software testing, software renovation, incremental algorithms, and attribute grammars.