Home1989 Treaties and Agreements ...Cameroon (89-406) – Treaty Concerning the Encouragement and Protection of Investment hide Cameroon (89-406) – Treaty Concerning the Encouragement and Protection of Investment TIAS Office of Treaty Affairs April 6, 1989 Trade and Investment Treaty signed at Washington on February 26, 1985 with annex. Entered into force April 6, 1989. Download attachment [17 MB] Tags Cameroon Trade and Investment Treaties