Elias Menachem Stein (January 13, 1931 – December 23, 2018) was an American mathematician who was a leading figure in the field of harmonic analysis.

[1] He graduated from Stuyvesant High School in 1949,[1] where he was classmates with future Fields Medalist Paul Cohen,[2] before moving on to the University of Chicago for college.

Stein worked primarily in the field of harmonic analysis, and made contributions in both extending and clarifying Calderón–Zygmund theory.

According to the Mathematics Genealogy Project, Stein had at least 52 graduate students—including the Fields medalists Charles Fefferman and Terence Tao—some of whom went on to shape modern Fourier analysis.

His son Jeremy is a professor of financial economics at Harvard, former adviser to Tim Geithner and Lawrence Summers, and served on the Federal Reserve Board of Governors from 2012 to 2014.