Abstract: French, C., Murphy, R. & Atkinson, M. (1999) Flora of Cornwall. Pp. vi + 400. Wheal Seton Press, Camborne. ISBN 0-9534613-0-0. Price £40 (hardback). Available on CD-ROM from Cornwall Business Systems, CBS House, Albany Rd, Redruth, Cornwall TR15 2HY, UK. Price £40. Just how useful are local floras? In the past few years, Britain has seen the emergence of many new county floras that represent an extraordinary effort of field survey on the part of (mainly amateur) botanists over the entire country. The question must be asked whether such effort is really worthwhile and whether the product (the published account) has real scientific value. The outcome of the field work usually takes the form of a series of distribution maps, annotated with comments on historical, geographical or ecological points of interest regarding each species. Maps may include grid lines, which assist in the precise location of records (as in the flora under review here), and they may contain backdrops of such features as geology (as in the Flora of Norfolk, Beckett & Bull 1999). In older floras, such additional items, intended for interpretative assistance, were supplied as transparent overlays. As production standards and techniques have improved, the inclusion of coloured plates has proliferated, as have attempts to interpret the flora in biogeographical, historical and ecological terms; habitats are listed and analysed and historical changes are documented. The value of the local flora is considerable. Perhaps its most obvious achievement is the mobilization and honing of local botanical skills, focusing the enthusiasm and ability (and often the parochial pride) of botanical communities on a specific objective. It seems that the county in Britain provides a geographical unit that is appropriate in scale to the needs of this kind of exercise. The published outcome provides a record of the current state of the county's plant life, and this in turn allows comparison with past (and future) surveys as a means of detecting changes in distribution patterns. In times when climate change and alterations in land use are much discussed, the record of the county floras will undoubtedly prove most valuable. The Flora of Cornwall attempts to provide such temporal comparisons by including in each map the pre-1980 records that are no longer to be found, thus supplying the first indications of shrinking distributions (although expanding distributions cannot be detected in this form). Perhaps the most outstanding feature of the Flora of Cornwall, however, is its availability in CD-ROM form. This is easily set up on an IBM-compatible PC with Windows 95/98. Quite apart from the capacity to call up any of the maps or text from the book, this facility also allows the selection of backdrops such as geology, river systems or grid squares and also provides access to more detailed historical data (precise grid references, dates and recorders are listed). It is also possible to check the occurrence of a species in a specific grid square. The CD ROM contains far more (high quality) colour images of the plants (which can be searched independently) and includes species maps for the Scilly Isles, which are not present in the printed version of the flora. There are, inevitably, some errors, such as the picture of Calluna vulgaris with the map of Ulex gallii, but the overall standard of production of the CD ROM is excellent. This is the first British and, as far as I am aware, the first local flora in the world to have used this particular facility. So, perhaps we need to extend our original question to ask whether the CD-ROM form of a local flora is worthwhile. The answer has to be yes, both because of the additional information that can be stored in this way and because of its accessibility and flexibility. You can quickly and easily ask questions of the electronic data base that would be difficult or impossible to achieve using the printed account. The authors are to be congratulated on this innovative approach to the documentation of a local flora. They have set a new standard for this type of venture and have also greatly increased the potential scientific value of such undertakings by opening up new prospects for the analysis and interpretation of all of these hard-won records from extensive field surveys.