Census data are used to monitor the efficiency of Bill 101 in reorienting language shift more favourably for French. Immigration from former French colonies or Romance-language countries is shown to be the major factor driving the increase in the share of French in the assimilation of Allophones since 1991. The schooling provisions of Bill 101 are seen to play a significant supporting role in this respect, but not those promoting French as language of work. It is further shown that the corresponding trend towards a greater share for French in overall assimilation has become seriously compromised by a growing Anglicization of Francophones themselves, notably in the Montreal metropolitan area. The resulting consolidation of the superiority of English as language of assimilation in Quebec is seen to explain in large part the emergence of a new language dynamic since 2001, combining a record decline in relative weight of Quebec’s French-speaking majority with a mild but equally historic increase in weight of its English-speaking minority.