This study explores causes of the deterioration in entry earnings of Canadian immigrant cohorts by estimating an empirical specification that nests a number of competing explanations found in the Canadian literature. The study uses the pooled sample of Canadian-born & immigrant men employed full-year, full-time from the complete 20 percent samples of the 1981, 1986, 1991, 1996, and 2001 Censuses. Explanatory factors examined include compositional shifts in the knowledge of an official language, mother tongue, region of origin, foreign education & credentials, and foreign labour market experience.