The text tries to analyse São Paulo's Pasteur Institute: a philanthropic scientific institution, founded in 1903 by psysicians from São Paulo, following the pallerns of Paris' Pasteur Institute. The institution's scientific and administrative hystory is focused within the context of the development of offjcial bacteriológicaI institutes founded in São Paulo's capital sincc the last decade of lhe 19a ccnlury. Because of lhe simifarity belween São Paulo's and Paris' insliíutes, we tried to make a counterpoint bctwcen lheórganizationalmodels of both instilutions, trying to infer from it what are lhe possibilities and limitations arising from lhe attempl lo rccreate an inslitutional paltern, wilhin a social formation which is diffe-rent from the one that originated it.