As a member of the French Historical School of economics,[1] Simiand predicated a rigorous factual and statistical basis for theoretical models and policies.

His contribution to French social science was recognized in 1931 when, at the age of 58, he was elected to the faculty of the Collège de France and accepted the chair in labor history.

Simiand moved further into the administrative apparatus of the French state during World War I when he left his position as a librarian for work in the Ministry of Armaments where he played a prominent role in making policy.

A student of Henri Bergson and Émile Durkheim, Simiand advanced a view of economics as a social science grounded in observable phenomena rather than convenient assumptions.

[2] Simiand's views on scope and method, which appear in La Méthode positive en science économique (1911),[3] were applied in his studies of real wages,[4][5] money[6] and long economic cycles.