THE HUGE expansion in museum building since the late 1960s is a phenomenon evident in many (west) German towns and cities, fostered by the regional organisation of German cultural affairs and the consequent atmosphere of local pride and rivalry. Frankfurt has been one of the prime movers in formulating a policy geared to augmenting the city's traditional cultural institutions. The opening of its new Museum of Modern Art is the culmination of ambitious plans laid over the past decade or more, which have resulted in some dozen new museums and extensions to existing institutions in the city.

In Frankfurt the wealthy industrialists' villas along the south bank of the Main - now predominantly owned by the municipality- have been transformed into new museums of film, architecture, Post and Telecommunications, to name but a few. Further along the bank, the venerable Stadel and Liebighaus museums have been renovated and extended. On the north side of the Main, the new Museum of Modern Art is visually linked with the Schirn Kunsthalle, housing temporary exhibitions. Beyond, is the single-space Portikus gallery, where a fascinating and innovative programme of contemporary art shows has developed over the past few years.

The Stadel extension, designed by Gustav Peichl and opened almost a year ago, has proved something of a disappointment- fussy in detail and unfortunate in scale. The top floor is designed to house the permanent collection (and includes several loans from the new museum across the river), while temporary exhibitions are mounted in the ground-floor galleries. Unfortunately, as the recent Max Beckmann and Bruce Nauman shows have respect- ively demonstrated, this ground-floor space appears too small to accommodate major touring exhibitions, but too large for more experimental shows of the type so successfully held at the Portikus. The dearth of contemporary art to fill the top-floor galleries raised questions about the Stdidel's r6le in collecting the art of today, while confirming the need for a new Museum of Modern Art.

Hans Hollein, the architect of the new Museum, has had the advantage from the outset of knowing its contents well. His celebrated museum at Monchengladbach reflects his view of the pluralistic tendencies of contemporary art, offering visitors a bewildering multiplicity of choices between one display area and the next. The singular site (the museum is integrated into a hillside) enabled Hollein to create strikingly individual spaces, many designed specifi- cally for works in the collection or on long loan. These values, modified to suit a very different site and collection, form the basis of the new Frankfurt museum. The visitor is again invited to choose a variety of paths through the galleries, connected by ramps and a Y-shaped staircase at the heart of this triangular site at the junction of the Braubach and Berlinerstrassen. The airy, Italianate central courtyard, from which all levels of the museum can be seen, is reached by a steadily rising series of stairs and ramps from street level. The external arcading, in local red sandstone, unfolds intimately either side of the corner entrance, providing a human scale (and an enliven- ing cafe) for an otherwise rather daunting fagade (Fig. 108). Within, rounded corners and spectacular vistas, both hori- zontal and vertical, are visually fascinating, but frequently distract attention from the works of art themselves. On the other hand, Giinther F6rg's enormous wall paintings in the stairwell marry to spectacular effect with the archi- tecture, while nooks and crannies, under staircases or carved out of the asymmetrical floor plan, house instal- lations by, among others, Nam June Paik, Lothar Baum- garten and Christian Boltanski.

The relationship between fagade and interior has occasionally fallen victim to architectural caprice. The series of concave and convex fan and bow windows are predictably disruptive to the display spaces. Hollein has created a stepped 'prow', complete with urns and pillars, at the sharp end of the site. Unfortunately, the windows specifi- cally inserted to allow appreciation from within disturb the visual lines of the dramatic triangular galleries, trans- fixing the visitor by their placement at the gallery's nar- rowest point (Fig. 109). Another detail is emblematic of the confrontation between architect and curator so often encountered in museum buildings. It was planned to erect a gold ball on a column outside the slim corner window of the Beuys gallery, with laughable consequences for the work. The orb has vanished, but the whimsical window remains, now masked with milk glass to reduce its visibility from within.

A core of around seventy works (mainly Pop and mini- malist, from the Stroher collection) had been bought for the museum by the city in the early 1980s. The new Director, Jean-Christophe Ammann, arrived in 1987, early enough to modify the master plan with his ideas about the expansion and display of the collection - including the use of many rooms for site-specific installations and environ- ments. The acquisition in 1986 of Beuys's monumental Blitzschlag mit Lichtschein auf Hirsch brought a further series of modifications to incorporate a diamond-shaped space over two storeys. Ammann has tried to find 'bridges' (primarily in the work of On Kawara, Gerhard Richter and Bernd and Hilla Becher) between the Str6her works and the art of the eighties and nineties, and has deliberately limited the overall number of artists represented in the museum. The work of some fifty was hung in the opening show, and others will be displayed in rotation.

The Museum has produced an impressive series of leaflets (unobtrusively sited in corridors) and publications. A series of monographs, 'Schriften zur Sammlung des Museums', examine in depth the groups of work in the collection, taking the place of aquisitions catalogues. Nearly twenty publications were ready in time for the opening and more will follow. Hubertus Butin's Zu Richters Oktober-Bildern on Gerhard Richter's Baader-Meinhof series, a permanent loan to the museum, is typical in its breadth and clarity: highly readable, it is aimed at the well-educated museum- going public on which German museums can count.