In Canada there exists a need to prepare the teaching force, which is primarily monocultural and monolingual, to work with an increasingly ethnoculturally diverse student population. This paper defines the term "ethnocultural," and presents three dimensions of ethnocultural knowledge that are essential to the ongoing professional and pedagogical development of preservice and inservice teachers. "Ethnocultural" has been chosen as a term that appears to incorporate all the facets that make up a person or a group. It encompasses ethnicity, or racial background, and the aspects of culture that include nuances of language, heritage, personal behavior, and self-identification, and it is free of the political connotations of the term "multiculturalism." Three key variables constitute the core meaning of the term: ethnicity, shared patterns of socially acceptable behavior, and language. Three dimensions of ethnocultural knowledge are required of teachers. These are the cultural, pedagogical, and sociolinguistic dimensions. The cultural dimension has often been emphasized, but the pedagogical and sociolinguistic dimensions deserve greater emphasis as teachers look for approaches that reach all students. (Contains 98 references.) (SLD)