Data collected during the Anchor Test Study norming phase were used to investigate substantive relationships between reading achievement and school, classroom, and pupil variables. School characteristics, such as location, public or private, socioeconomic level, and percentage minority enrollment, were found to be related to achievement in reading as measured by the Metropolitan Achievement Tests. Reported IQ, race or ethnicity, primary language, and the diagnosis of a reading problem were significant correlates of reading achievement. Ability grouping and class size, the classroom variables studied, were not related to reading proficiency. The interrelationships among selected pupil and school characteristics were analyzed in addition to the univariate relationships of pupil variables to reading achievement. An overview of the Anchor Test Study and detailed descriptions of the methodologies used in the present study are provided. (EVH)