This Norton Critical Edition remains the only edition available that is based on completely re-edited texts, accounting for all versions that Twain might have written or influenced. All substantive variants in the two separate "first editions," one printed in Britain and the other in the United States, have been reconciled in this collated edition, with all rejected variants tabulated. Dozens of additional illustrations accompany the text, and all textual variants, accepted or rejected, are included. 

"Criticism" includes twenty-three reviews and interpretive essays, eight of them new to the Second Edition, including those by Andrew Jay Hoffman, Myra Jehlen, and John Carlos Rowe.

A Selected Bibliography is also included.