I do not agree with the order that all employees must use English as a common language in the company in Japan. If the companies trades with overseas company, and has foreigners of employees in their office, English is required for the business. But except for exemplified above, most Japanese workers are not necessary to use English in their jobs. Because their co-leagues are mostly Japanese people, Japanese language causes to less miscommunication than English that they are not used to.
 Fortunately, Japanese workers obtain lots of information they want through Japanese language owing to many literatures written by it. This is a difference between in Japan and in other countries that their employees who are also not native English speakers need learn English for their work.
  Despite no need English for the employees, it is very stressful for them to be imposed learning English on in the company. It may lose competent workers who have capabilities for their specialized parts by the reason why they merely cannot use English. There is no benefit both the company and the employee.
  Thus, as long as Japanese workers work in Japanese company, they do not need English. If a company wants its employees to learn English, that should be carried out from earlier education stage such as college or high school not from a company.
 

http://www.english-online.at/news-articles/business-economy/japanese-managers-tell-employees-to-learn-english.htm