Europe

Denmark

? http://denmark.usembassy.gov/other_services/renunciation-of-citizenship.html

Greece

? http://athens.usembassy.gov/renunciation.html

Germany

? http://germany.usembassy.gov/acs/citizenship/renounce/

The Netherlands

? http://amsterdam.usconsulate.gov/dual_nationality2/renunciation-of-u2.s.-citizenship

Norway

? http://norway.usembassy.gov/renounce.html

Switzerland

? http://bern.usembassy.gov/service/renunciation5.html

United Kingdom – (Great Britain)

? http://london.usembassy.gov/cons_new/acs/passports/renunciation.html