The role of the school board in public K-12 schools is considered from the agency and the stakeholder perspectives. A new theoretical model for the school board members practice of due diligence encompassing content and process issues is developed from empirical literature on agency and stakeholder relationships, vision content and process, and strategy-making process capability. A four pronged methodology is used to test the model and resolve research issues on the practice of due diligence: 1) Development of an accountability measure of student performance using the Accountability Report from the New Mexico State Department of Education; 2) Testing of 10 propositions and 7 hypotheses using case studies of seven districts, survey results of 89 district board presidents and superintendents, and the measure of student performance; 3) Determination of existence of due diligence through case studies of seven school boards; 4) Comparison of existing models of due diligence with the literature based model. The sample is all New Mexico Public K-12 school districts. Case studies focused on monitoring of district educational and financial plans and the coherency between the two plans. The surveys were replications of Larwood (1993,1995) et al on vision and Hart/Banbury (1994) on strategy-making process capability. Key findings: 1) Uniform accountability measures are available for all districts in the state but case study districts used these selectively with regard to student performance measures; 2) Board presidents and superintendents were capable of articulating a vision for the district but vision alignment was not evident; 3) The New Mexico board/superintendent contract is a behavioral versus performance contract. Diagrams of the theoretical and New Mexico models are included along with a revised model of due diligence. Recommendations for training school boards include the use of questions provoking examination of board practice leading to improved student achievement.