Corruption appears to be destructive to investment arbitration and the international
development as a whole. In some states to engage in corruption is a typical method of conducting business
in investment or trade. There are two forms of bribery regarding international investment. One of them is
that when an investor corrupts public official to get a suitable investment agreement, another is where the
investor is blackmailed to pay money by a person who has authority. The paper aims to evaluate whether
international investment arbitration as a source of dispute settlement might be used to combat bribery in
foreign investment. Also, the paper focuses on a controversial issue when host states may use corruption
as a defence in investment tribunals. As an example, a case the World Duty Company Ltd v Republic of
Kenya has been given to explain the defence by the host state. One may expect that this case is able to
change approach taken by previous arbitrators.