The Michigan Department of State Highways and Transportation is in the process of developing a motor vehicle emissions inspection and maintenance (I/M) program for implementation in various nonattainment areas of the State. To date, the effort has focused on identifying and assessing the various program alternatives available that satisfy the objectives of I/M. A primary issue at this point concerns whether the program should use the emissions measurement concept, or a concept involving parameter inspection. Assessments of the specific requirements related to implementing I/M in Michigan, including a first level assessment of alternative program approaches, have been developed as part of this initial planning. Based on these initial assessments, the need for a more detailed assessment of the parameter inspection concept was identified. These detailed analyses of issues related to the parameter inspection concept were performed. These analyses considered the emissions reduction potential, costs, consumer and repair industry impacts, and administration requirements of four parameter inspection concepts. The results of these analyses are reported here.