Since 1975, Ontario teacher negotiators have focused attention on conditions-of-employment clauses. This paper focuses on those clauses that have direct or indirect cost implications for school boards as enrollments decline. These clauses concern such issues as pupil-teacher ratios, class size, and job protection. Information for the analysis was gathered through interviews with Toronto teachers, board members, and administrators as well as from statistical data from the Education Relations Commission. The paper examines changes in the incidence and content of conditions-of-employment clauses since 1975. The rising incidence of conditions-of-employment clauses suggests that teacher negotiators are making substantial gains, with secondary teachers making the most gains, elementary teachers second, and private school teachers third. However, the content of these clauses shows that boards have maintained a high degree of flexibility in determining staffing needs and that the cost increases for boards have been fairly small. In the future, it appears there will be continued pressure for clauses directly related to declining enrollments and staffing flexibility, but real gains will be modest in size and slow in coming. (Author/JM)