Williams Scotsman announced in August 2004 an international expansion with new activities in Europe and Mexico. The company founded Williams Scotsman Europe, S.L., to acquire a minor interest in Wiron Prefabricados Modulares, S.A., privately owned, in Parla, Spain, near Madrid. Wiron owned several thousand modular units that the company leased through offices in all major cities in Spain. Williams Scotsman was given a seat on the board of directors to learn more about the company and its operations in Spain and was granted the right to refuse to sell other Wiron shares. In Mexico, Williams Scotsman opened its main office in Mexico City and a branch in Monterey. The company seized national distribution opportunities by entering into an agreement with SaniRest, a large waste disposal company with 27 branches in Mexico. Williams Scotsman has begun offering value-added services to its customers. In response to customer requests, Williams Scotsman offered its customers a security system for mobile phone technology for temporary or permanent structures through an exclusive agreement with Tattletale Portable Alarm Systems. The safety system was of particular interest to construction companies who wanted to protect machines from theft.
For her modular construction clients, Williams Scotsman offered to watch the project in real time via a web camera service. Inet OnSite allowed customers to inspect the construction process without having to go to the site, saving time and money, especially if they were not in town. The service has doubled as security surveillance. William Mobile Offices, founded in 1944, originally sold construction trailers small enough to be towed by a car. Later, the company began selling and leasing dual-width mobile office structures. In the 1960s, the company expanded for the first time outside the Baltimore area with branches in Atlanta and Chicago. By renting out its distinctive green green mobile structures, Williams has developed commercial activities along the East Coast and in the Midwest. In the 1980s, Williams began manufacturing and installing modular office structures. Although no less expensive than construction offices, modular construction has provided a rapid construction process that has significantly reduced the construction time required. Contrary to the stereotype, modular structures could be designed with exterior views of masonry, stucco, wood and brick, taking into account aesthetic considerations, such as the architecture of the surrounding commune. Williams proposed modular one-story or multi-storey office structures with intricate architectural dimensions and interiors such as fine cherry paneling.