She has been the head of the Statistics division at the Research Department in the Bank of Israel, and from 1999 to 2003, she was the president of the Israeli Association for the Study of European Integration.

Her first works in economic history were on 18th century England and are where she developed previously nonexistent data on the balance of payments of the UK.

In Brezis's work with Krugman, they emphasized that endogenous-growth theory suggests that technological change tends to reinforce the position of the leading nations.

On government policy towards technological development, Brezis argues that the method used for financing projects is too conservative: Peer review mechanism has a clear bias against innovative ideas.

Brezis and Warren Young have studied together the new views on demographic transition, in which they reassess Malthus and Marx's approach to population.

with Peter Temin, North Holland, Elsevier, 1999 "The Role of Higher Education Institutions: Recruitment of Elites and Economic Growth" (with François Crouzet) in T. Eicher, eds.

The Effects of Higher Education on Social mobility at the Top" "Leapfrogging in International Competition: A Theory of Cycles in National Technological Leadership."

"Technology and Life Cycle of Cities"(with Paul Krugman), Journal of Economic Growth, December 1997, pp. 369–383.

"The New views on Demographic Transition: A Reassessment of Malthus's and Marx's Approach to Population" (with Warren Young), European Journal of Economic Thought, 2003, 10: 25–45.

"Britain's Balance of Payments in the Century before Waterloo: New Estimates, Controlled Conjectures", Economic History Review, February 1995, pp.

“The Role of Assignats during the French Revolution: Evil or Rescuer?” (with Francois Crouzet), Journal of European Economic History, April 1995, pp. 7‑40.