A pilot In-School Suspension Program was inaugurated at one junior high and one senior high school in Montgomery County, Maryland, during 1980-81, in order to provide an alternative to out-of-school suspension. To assess the pilot program's effectiveness, an evaluation study examined rates of and reasons for in-school suspension, length of such suspension, race of suspended students, educational disruption, and recidivism. It was found that the pilot schools made extensive use of the in-school suspension alternative, particularly for less serious disciplinary offenses. However, while teachers and students reported feeling that the program was effective, students with more serious suspension records did not agree. Additionally, relatively high recidivism of students whose first suspension was in-school suggests that negative parental reaction to out-of-school suspension is a major deterrent to student misbehavior. These findings, along with the confirmation for suspended students, indicate that in-school suspension is a viable disciplinary alternative but that several areas require monitoring: (1) students' completion of class assignments while suspended; (2) parental involvement in the in-school suspension process; (3) increases in the overall suspension rate; (4) racial differences; and (5) greater recidivism after in-school suspension. (Author/GC)