L'Union is one of the most important urban renewal projects in France. Once predominantly industrial, this 80-hectare site is now more or less free of its former buildings. L'Union is a piece of the city to be created, invented, and woven into the existing urban fabric. Exemplary in terms of sustainable development, the urban renewal project calls for strong interlocking of housing and economic activities.
L'Union, the first eco-quarter in the Lille Métropole, is in line with a policy of sustainable development both in its development and its future management: Remediation of pollution on the plots, limitation of waste production, organisation of the water cycle, management of mobility, participation, etc.
As a hub of economic excellence, l'Union plays a part in the economic revitalisation of the Lille metropolitan area, and more particularly its northeast side, one of the densest in the conurbation. The economic dynamic of l'Union is organised around two areas of excellence. The first is centred on image, culture and media and the second is dedicated to innovative textiles.
A vast construction programme of 1,400 new housing units is also planned for l'Union. These units - individual or collective - will be offered either for purchase or lease, with leased subsidised housing accounting for 30% of the total number. Eventually, l'Union will be home to 3,000 employees and 3,000 residents.

The seven places of l'Union
La Tossée is designed as an “interior”, where the spaces are integrated and designed within a single whole, without systematic definition of the plot or of the street, but in the spirit of a community of spaces and services (parking, management of water, waste, energy, etc.) The continuity of the narrative of the Cité Tossée creates a palimpsest on the warp and weft of the past whose fabric becomes part of the contemporary city.

Thus the notion of “street” identified in the Master Plan fades and is reintroduced into “courtyards”; the logic of spaces that are served and spaces that serve leaves room for a tangle of uses and services. The former rails and the ground paintings are the only “Ariadne's threads” of past and present journeys, in a patchwork of materials without “hems”.
The seven places of La Tossée, then, are not determined by their status (public, private or shared) but by new usages, vestiges that are reused, ambiances that pre-exist and can be reinterpreted–rewritten.
Seven “families” of places are identified in this way. Each contains spaces that share characteristics of use and of form (courtyards, passages, gardens, scenographic spaces, etc.). Therefore they adopt shared characteristics as regards ground treatment, lighting, introduction of greenery, etc.