The World Cat Discovery search interface is available in fifteen languages: English, Czech, German, Spanish, French, Italian, Dutch, Maori, Swedish, Portuguese, Japanese, Korean, Thai, and Simplified and Traditional Chinese. Across the bottom of the Advanced Search screen, you will notice the option to change the interface language.
Note that changing the interface language does not affect the result set. For example, switching from English to French does not alter search results so that only French-language materials, or materials available from libraries in France, are displayed. The items presented to a user for a particular search remain the same regardless of the interface language.