This article describes the policy of internationalization conducted by Lyonnaise des Eaux (renamed Suez) and it focuses on the internal transformations during the period from 1980 to 2004: the stages in these changes, the organizational characteristics and the principles that were applied. The central argument is to consider that this company has, over the period, designed a new type of organization which combines a deep center and the operation of many different operating units based in a large number of countries. It has thus become a “local-global” firm; different from existing types (H, U, M, J) of firms. This new form has four characteristics: the central role played by local units, procedures of reporting towards a compact center, assistance from the center, and direct exchanges between local units following a “principle of connectivity”. This discussion of the specificity of the large firm with institutional properties is related to a general history of large firms and it contributes as well for a theory of change. It leads to revising the well-established dichotomy between Institution and Market as this type of firm borrows from both fields.