Besides being responsible for distribution and sales, they also act as agents for domestic makers in importing raw materials, parts, and machinery and in providing capital and financial services.
由於日本商社的背後都有龐大的財團支持，甚至擁有自己的銀行，他們挾雄厚的資金，直接對國內廠商進行投資，或提供融資服務。例如一家資金不足的食品罐頭工廠想要擴充設備，就向日本商社貸款，並由其在國外代尋合適的機械進口，隨後並將產品交由商社銷售。