For the duration of the Dan Flavin retrospective (until 2 April), the large foyer through which you enter the Hayward Gallery is bisected by a barrier of identical rectangular units, each mounted with four fluorescent tubes. They form a glowing, waist-high wall of green light which blocks the way to the ramp leading to the upper level. Objects shown in this foyer, despite its considerable size, tend not to seem part of the rest of an exhibition. The ramp draws you on and you pass quickly (often too quickly) to what comes next. The green wall's disruption of normal circulation is an admirable piece of exhibition craft. It forces a pause in which the syntax of what will follow is established.

LRB 23 February 2006 | PDF Download