This study focuses on the manuscript sources for one of Beethoven's most popular piano sonatas, the Op. 57 in F minor, known as the `Appassionata' (1804-06). It presents transcriptions of all the known sketches for this work and evaluates them in terms of their specific stage of evolution and their relationship to the final version. The initial chapters, which incorporate the analytic vocabulary proposed by Jan LaRue, summarize salient points for each movement, and serve as a basis for the sketch discussions. The detailed sketch analysis explores such topics as harmonic rhythm, phrase structure, and climax planning. Facsimile reproductions of the sketches allow scholars to compare the transcriptions with the originals. The author also examines eignificant revisions of the finale in the autograph.