This paper, addressed to public school employers, discusses lessons to be learned from the Wisconsin Legislature's passage of a 1978 law known as mediation-arbitration, which allows employers and unions to agree to an alternative voluntary impasse procedure to the one set forth in the statutes. First, the paper discusses the history of the agency shop (fair share agreements), and binding arbitration. Next, it discusses the mediation-arbitration law, which, it says, has worked to the detriment of public employers. The paper says that of the decisions handed down in Wisconsin, the unions have won the majority of cases involving fair share. To avoid this, employers must create and maintain an effective lobbying organization at the legislative level. They also should see the advantage of allowing municipal employees in small school districts the right to strike rather than forcing compulsory arbitration on them. Finally, employers should evaluate the concept of legalizing compulsory union dues and then subjecting them to binding arbitration. (Author/LD)