bussproofs, version 1.1. Proof trees in the style of the sequent calculus and other proof systems. The package allows the construction of proof trees in the style of the sequent calculus and many other proof systems. One novel feature of the macros is they support the horizontal alignment according to some centre point specified with the command \fCenter. This is the style often used in sequent calculus proofs. The package works in a Plain TeX document, as well as in LaTeX; an exposition of the commands available is given in the package file itself. Documentation is also given in a separate LaTeX/FILE, BussGuide2.tex/BussGuide2.pdf. Distribution under the LaTeX Project Public License The CTAN distribution includes: bussproofs.sty - version 1.1 of the style files. BussGuide2.pdf - The documentation by Peter Smith. BussGuide2.tex - LaTeX source for the documentation. testbp2.tex - A file used for testing, with examples of usage. testbp2.pdf - The output of the testbp2.tex README.txt - This file. Maintained by Sam Buss sbuss@math.ucsd.edu