The present study does not attempt to present a complete or exhaustive survey of the myriad spatial orchestrational devices occurring in the symphonic and operatic repertoire. Rather, the study is limited to an examination of the specified use of the trumpet as an offstage instrument in selected representative works. The study's purpose is to identify trends in the use of this orchestrational device, to serve as an aid to the trumpeter in matters of interpretation, and to provide a practical reference for the solution of acoustical and technical problems common to the performance of spatially conceived music in the orchestral literature.