The Haydn Trumpet Concerto and the Hummel Trumpet Concerto are two of the most important concertos in the solo trumpet repertoire and the cadenza reflects the performer's personality and technical abilities. There have been numerous recordings of the two concertos and they are consistently used in performance and as a pedagogical tool. This document contains both published cadenzas and transcriptions of recorded cadenzas from the first and last movements of the Haydn Trumpet Concerto and the Hummel Trumpet Concerto.This study begins with an investigation of the concepts and historical information related to the keyed trumpet and classical cadenzas. It includes a discussion of the historical significance of the keyed trumpet, brief biographies of Anton Weidinger, Joseph Haydn and Johann Hummel, and a study of the stylistic traits of cadenzas of other brass instruments from the classical period.Following the introductory five chapters, chapter six contains the compilation of transcribed and published cadenzas. The cadenzas are cross-referenced in a table located at the beginning of the chapter. Each cadenza includes information about the recording and/or publisher from whom the cadenza is available. The cadenzas were transcribed from recordings, transposed for Trumpet in E-flat and entered into Finale 98.This study is meant to be a reference tool that performers and instructors can employ for the study and performance of various cadenzas. The writer hopes that this collection will provide inspiration and will serve as a guide for those who wish to compose a personal cadenza that highlights their own strengths and preferences. / School of Music