The purpose of this study is to provide a guide for the instruction of a trumpet mariachi performance ensemble in a music curriculum. The fulfillment of this purpose is dependent upon the data supplied in answer to the sub problems: (1) What socio-cultural information provides authentic trumpet mariachi music; (2) What trumpet mariachi literature illustrates the repertoire and style; (3) What instructional source materials may be developed such that Mexican American and non-Mexican American instructors build a competency in repertoire and style; (4) How could this guide be evaluated in its functional design for a music curriculum? The data collected for use in this study has been presented in three major categories: (1) the history and milieu in which the trumpet, mariachi crystalized; (2) the repertoire--its history and function in Mexican society and the transcriptions of types demonstrating the musical structure; and (3) the technical information relative to the instruction of the particular mariachi instruments. An evaluative instrument has been supplied in an attempt to establish the validity of the information and examples provided in this practicum. The validity of the research seems to rest on its authenticity and its serviceability. The findings of this study are stated as assertions …