The contention of the thesis is that the adoption of a new analytical premise with respect to the role of tonality in Beethoven's music is necessary to the true appraisal of this aspect of the music. The main focus of the material presented is a detailed examination of the initial thematic treatment in relation to four major keys and comprises four tonal-thematic analyses (Part 11. The Supplementary Volume comprises the Thematic Indexes. relevant to the Part II examination and reference to that Volume is integral to the tonal-thematic analyses. ) Fart II thus treats a defined area within the music. Prior to this examination the subject as a whole - tonality and the role of tonality in Beethoven's music - is discussed in the Introduction (Part Iv Section I), and material basic to the entire investigation is presented (Part I. Section II). Part III consists of the Conclusion to the thesis enquiry, The two Appendices treat two topics which although not within the scope of the main thesis investigation, are nonetheless relevant to the subject as a whole; these are the tonal relationship Bý/G in the music and the "Second Group" key in minor mode usage.