Maryland School Performance Assessment Program (MSPAP) assessments are criterion-referenced performance tests designed, developed, and implemented by the Maryland State Department of Education in collaboration with classroom teachers and other Maryland educators. MSPAP is the major strategy for implementing Maryland's educational reform initiative. It provides information relevant to assessing school performance and guiding school improvement plans and activities. The primary focus of the information from the MSPAP is schools, although information about individual students is available. In June and July 1998, approximately 188,000 student answer books were scored. This technical report contains information about: (1) test development; (2) test administration; (3) scoring; (4) special issues related to mathematics, algorithmic scoring, and student participation in MSPAP; (5) scaling and equating; (6) reliability; (7) validity; (8) score interpretation; and (9) the MSPAP score reports. Three appendixes contain test maps, information on the number of items comprising each outcome, and scale score ratings from each MSPAP proficiency level. (Contains 29 tables and 29 references.) (SLD)