David "DC" Collier, 44, from Britain, could not speak a word of Japanese when he first came here seven years ago.

Not only has Collier, president of mobile phone game company Pikkle, become conversant in Japanese, but he conducted e-mail correspondence with The Japan Times in Japanese and reads game-related blogs in Japanese. He credits his ability to owning a company.

"You can live in Tokyo without speaking Japanese, but it is very difficult if you set up a venture company," he said. "Very few employees can speak English in my company."