The purpose of this study was to identify the professional actions of
early French immersion teachers in the classroom and to ascertain teac
hers' judgment regarding the effectiveness of these actions. Critical
Incident Technique was used to gather professional actions from teache
rs and their school principals. The majority of professional actions i
dentified by the immersion teachers referred to the management of voca
bulary instruction through the use of systematic instructional strateg
ies across the school curriculum. One of the implications drawn was th
e need for a distinct teacher preparation program for teaching in a se
cond language context. Sheltered programs for the preparation of prese
rvice teachers in all areas of the school curriculum were suggested to
upgrade their linguistic abilities in the various subject areas.