This paper reports the results of a study of 1,300 special education students attending 81 elementary, middle, and high schools in Massachusetts that examined the patterns of variation in services delivered to students with disabilities in relation to student characteristics. Results of the study indicate that the majority of these students spent some portion of their time in regular classrooms. Almost 57 percent of the students served were in nondepartmentalized environments and spent some portion of their week receiving services from regular self-contained classroom teachers. Many students with disabilities received special education services while in the regular classroom. In many cases, the data suggest that these special education teachers served both special and regular education students while in these classrooms. More than 34 percent of the students with disabilities in nondepartmentalized environments were served in special classes, and almost 39 percent are served by a special education resource teacher in a resource room. For the majority of students served in nondepartmentalized and in departmentalized settings, approximately one-third of the per pupil costs of serving students with disabilities are generated within the regular classroom settings. For ungraded students, this percentage of expenditure accounted for in the regular setting falls to around 7 percent. Although only small percentages of students are involved, it appears that often students with more severe disabilities receive other specialized or extended care services from nurses, health professionals, personal nurses, aides, or other family counseling and social services. (CR)