In making his gift, Lawrence asked:[6] But where can we send those who intend to devote themselves to the practical applications of science?

By the late 19th century, the School faced increasing competition from the Massachusetts Institute of Technology (MIT) and was constrained by the uncertain views about its role and status by the long-serving Harvard President Charles William Eliot.

[7][better source needed] As a result of such uncertainty, the Lawrence Scientific School became less of an independent entity, losing its influence and students to other parts of the university.

Harvard President James Bryant Conant created what was known as "Conant's Arsenal", a research hub for defense-related engineering projects including radar jamming, night vision, aerial photography, sonar, explosives, napalm, and atomic bomb research.

[11] One notable project from this era was the Harvard Mark I computer; one of the first programs to run on the Mark I was initiated on March 29, 1944, by John von Neumann, who worked on the Manhattan Project at the time, and needed to determine whether implosion was a viable choice to detonate the atomic bomb that would be used a year later.

[21] The faculty has particularly close ties (including joint appointments) with the FAS departments of Physics, Earth and Planetary Science, as well as Chemistry and Chemical Biology.

The campus provides 600,000 square feet (56,000 m2) of interconnected labs, classrooms, clusters, and offices in six buildings.

[22] SEAS is expected to expand into the new Science and Engineering Complex (SEC) under construction in Allston, across the Charles River from Harvard's main location in Cambridge.