business term meaning mutual friend/acquaintance
A chukaisha plays an essential role in the introduction of one business-person to another, as the western practice of "cold calling" is frowned upon in Japanese commerce.
If you're looking for contacts in Japan, always try fo find someone to introduce you to your quarry. This will give you a higher degree of respect when you eventually meet your target.
REFERENCES: Passport Japan (Dean Engel & Ken Murakami, ISBN 1-885073-17-8) & personal experiences.