Arbitration decisions resulting from school district disciplinary actions and professional employee grievances are studied to determine the extent to which school district decisions are upheld by arbitrators, and to identify factors for the support, modification, or contest of a district decision. Data sources are 333 arbitration cases from 27 states and the District of Columbia that were voluntarily reported to the Labor Relations Press during 1972-1987. Case scope, categories of offenses, district actions, and arbitrators' decisions are presented and compared by 4-year periods. Changes in the types and frequencies of arbitrated offenses reflect a decrease in cases involving teacher competency and an increase in conduct grievances. Although an increasing number of school district decisions have been upheld, arbitrators rule against districts a majority of the time. Findings indicate that the number of least severe corrective actions has decreased significantly, accompanied by an increase in the number of most severe sanctions. Collective bargaining's grievance procedure has changed the focus of employee management from competence to conduct that results in competence. Tables provide statistics that support the conclusions. (9 references) (LMI)