Sao Tome and Principe
approved March 1990, effective 10 September
1990

Saudi Arabia
governed according to Shari'a law; the Basic Law that
articulates the government's rights and responsibilities was
introduced in 1993

Senegal
new constitution adopted 7 January 2001

Serbia
10 November 2006

Seychelles
18 June 1993

Sierra Leone
1 October 1991; subsequently amended several times

Singapore
3 June 1959; amended 1965 (based on preindependence State
of Singapore Constitution)

Slovakia
ratified 1 September 1992, effective 1 January 1993;
changed in September 1998 to allow direct election of the president;
amended February 2001 to allow Slovakia to apply for NATO and EU
membership

Slovenia
adopted 23 December 1991

Solomon Islands
7 July 1978