This is the first publication of Sergei I.Taneyev's cadenzas to the 1st and 3rd movements of Mozart's Concerto in Е flat major for two pianos and orchestra (К 365).
The manuscript of both cadenzas, written in 1890, is kept at the Department of Rarities of S. I. Taneyev Research Library at the Moscow Conservatory. The edition, prepared bу Professor of the Moscow Conservatory А.М. Merkulov, includes the facsimile of Taneyev's manuscript and the printed musical text, as well as а comprehensive preface and description of the manuscript. Both the preface and the description will help the reader to understand the great Russian master's creative attitude and to detect the features of his personal style.
This publication is addresed to professional performers and piano teachers, to students of musical colleges and conservatories, as well as to musicologists.

CONTENTS
1. А. Merkulov. "То Combine the Perfection of Mozart's Writing with Contemporary Harmony"
2. S. Taneyev. Cadenza to the 1st movement of Mozart's Concerto (К 365)
3. Cadenza to the 3rd movement of Mozart's Concerto (К 365)
4. Supplement by V. Gryaznov. Version of the ending of the cadenza to the 3rd movement
5. Facsimile of the manuscript
6. On the autograph and the principles of the present puЫication