From the beginning he linked sociology with ethnology in the tradition of de:Lorenz Löffler, Richard Thurnwald and Wilhelm Emil Mühlmann.
Elwert was admitted to the Académie des sciences d'outre-mer, in Paris, as an associate member in 2004.
In his work on development cooperation, Elwert criticized the common reference to mere cultural differences, which obscures deeper socio-economic and political inequalities.
As a member of the Bielefeld development sociologists working group, Elwert made a significant contribution to the so-called "Bielefeld approach", which was trend-setting for German development sociology at the time.
[2] In 1993 Elwert was co-founder of the Berlin-Brandenburg Academy of Sciences and Humanities, three years later he became the editor in chief of the renowned journal Sociologus.