The 3Y2-inch floppy disk which accompanies this booklet is a standard DSIHD 1.44MB disk formatted by Microsoft (R) MS-DOSTM. The disk contains five files, all called ecpe (standing for Electronic Comparative Plant Ecology). All five have identical content but differ in file type. Only one of these files need be selected by the user, according to the software which will be used locally to examine the data. Filename Software ecpe.txt ascii text only, for MS-DOSTM ecpe.csv comma-delimited entries, ditto ecpe.xls for Microsoft (R) Excel 5.0 ecpe.wk3* for WK3 format in Lotusl-2-3 (R) ecpe.csm comma-delimited for Macintosh (R) *this file is accompanied by the usual ecpe. fm3. The Electronic Comparative Plant Ecology 1 INTRODUCTION This publication consists of a collection of standardized autecological information for the more common vascular species of the British flora. It is an amalgamated, electronic copy of the data tables which concluded both of the printed works Comparative Plant Ecology (CPE) and The Abridged Comparative Plant Ecology (ACPE).