Over the last decade enormous advances 10 our understandmg of the functionmg of "tomata have been made Today, the overall pattern of events 10 stomatal functloOlng IS generally under~tood although some of the fmer details of the mechaOlsm remam to be eluCIdated However, the mechaOlsm whereby changmg CO levels wlthm a leaf control stom­ 2 atal movements remam~ one of the biggest puzzles The excellent text PhYSlOlogy of Stomata, by Professors H Meldner and T A Mamfleld, I~ over 12 years old and mevltably sections of It are now outdated Although numerou~ flOe review,> on vanous aspects of stomata have been wntten 10 the meantime, none could be conSidered as complete, compact appraisals of the subject dnd thus to have super­ seded the Meldner and Mansfield book Now IS therefore an appropnate time to review the statu~ of our knowledge about stomata This book encompas~es all a~pect~ of the subject except the phySICal processes mvolved 10 the exchange of gases between a leaf and ItS envI­ ronment ThiS topIC IS dealt With very adequately 10 a vanety of other books and reVlew~, and the subject matter, With mmor differences of opmlon, remams much the '>ame today as It was perhaps 20 years ago A descnption of how to measure stomatal apertures and the use of porometers has been restncted to a fmal chapter whICh also deals with expenments which can be carned out by students Agam, there are