Since the Ontario (Canada) legislation in 1975 that formalized collective bargaining for teachers, public concern has focused on collective bargaining as the possible cause of recent enrollment declines and increases in schooling costs. However, according to Ontario provincial statistics, enrollment in elementary schools had begun to decline before the legislation and in secondary schools at least 2 years afterwards. If some of the bargaining provisions had increased costs by protecting teachers' jobs, the effects should be reflected statistically as changes in the pupil-teacher ratio. A comparison of government figures, though, shows that reductions in pupil-teacher ratios occurred before the introduction of formal collective bargaining and in the midst of increasing enrollments. The raise in average annual salaries of Ontario teachers has actually been furthered by the generally increasing experience and qualifications of the teaching force--attributable to declining enrollments, fewer entry-level teachers, and increasing seniority of remaining teachers. Overall, the costs of negotiated salaries since 1975, though increasing substantially, show gains commensurate with the Ontario work force as a whole, so that collective bargaining can be said only to have prevented deterioration in the relative level of salaries. (JW)