It depends
Postado por Silvana Wasitova em Suiça forum
Roula,
it depends on where you want to live/work in Switzerland, your field of work, and your employer/clients.
Geneva is quite international, many people can get by with English only, and live and work in English. Would also work in a multinational corporation that uses English as their official language.In general, and in other cities in Switzerland, you'll be much better off knowing the local language.
Good luck!