Social grace.

In a drive to modernise social services, the French ministry has been given purpose-built offices designed to express a gentler more democratic attitude to the needy.

French social services, among the most generous in Europe, are dear to the national heart, and Chirac's intimation last year that their scope was to be reduced provoked immediate crippling strikes. In spite of them, reforms of the system and its administration, as well as improvements of the building stock, are taking place. The French ministry of social affairs - the Inspection Generale des Affaires Sociales (IGAS) - is being overhauled and restructured. In the drive to make it leaner and fitter, IGAS's headquarters in Paris has been given new purpose-built offices. Designed by Alain Moatti and Jacques Moussafir, they have been inserted with great ingenuity into the third and fourth floors of a 1930s building packed into the dense fabric of the 8th arrondissement. Within the more or less unbroken shell of the building, the architects have contrived a lyrical and coherent plan creating luminous offices that are very far from the kind of Kafkaesque utilitarianism you associate with such an organisation.

From most points of view, the existing building hemmed in by undistinguished neighbours was not promising. Though arranged around a central courtyard, the floors were enclosed on two sides by 160 m long walls that were mostly blind. The average depth of about nine metres meant that natural light from the courtyard penetrated the building to a depth of about five metres on each level leaving a wrack of dark space around the periphery.

The solution to the problem of how to make civilised sense of all this was suggested by the structure of the organisation. IGAS's staff is made up of 50 desk-bound employees (including secretaries, management teams and administrators) and a hundred peripatetic inspectors who work in groups which swell and contract, and move as work dictates.

The basic plan is the same on both floors, the main variations being the library on level 3 and the cafe on level 4. Desk-bound staff were allocated naturally illuminated conventional offices with windows on to the courtyard. Around these offices, the architects have slung an inner wall like an enceinte that tracing an elliptical path defines the circulation and creates an internal gallery binding the separate spaces together. On plan, this is a sweeping gesture; it breaks the spatial monotony and suggests a dynamic force at work around a still central eye. Curious alcoves cling to its inner side and meeting rooms of various sizes seem spun out to the edges, filling out interstices and uneven spaces. By visualising space within a rigid rectilinear shell as being layered back in concentric bands from the central source of light, the architects have been able to combine, and yet make plain the static and dynamic parts of the organisation. The arrangement is clever and having at its source the deployment of light, it lends itself to a lyrical exposition.

Volumetric juxtapositions, inventive combinations of materials and luminous colours are used so as to make the most of natural light from the main courtyard, and from small courtyards that illuminated the old lavatories. Each level has been assigned a different colour: ultramarine blue for level 4 and glowing yellow for level 3.

The range of inspectors' rooms is wide. There are desks for individual study within the library and in the six alcoves on both levels, while meeting rooms number from eight people upwards, to 30 in the largest conference room. The architects imagined the gallery to be a town arcade, animated by people moving about their business, meeting each other or working quietly by themselves half hidden from view within an alcove.

Offices next to the main courtyard have glazed walls on to the gallery, and daylight is taken into the depths of the building by being diffused through these opalescent walls of sandblasted or coloured glass.

Natural light supplemented by skilful artifice is caught by light-reflective surfaces on walls and ceiling, and by gleaming floors of coloured resin; to break up the monotony of large expanses of ceiling in the bigger meeting rooms and library, suspended metal ceilings conceal and enhance artificial lighting.

Inset in places into the thickness of the curving gallery wall are document cupboards, finished externally with a liquid rubber coating, coloured and treated to give it the iridescent quality of velvet. The same finish has been used elsewhere, on doors and even work surfaces. Furniture by the practice, like library shelving in solid wood and galvanised steel, expresses pleasure in materials and pays attention to ergonomics.

One qualification of this intelligent imaginative scheme is that materials that transmit light, also transmit noise; but this is no more than background buzz, like the familiar noise of people in a street. P.M.