Abstract: Retrospective review of cases of suicide involving helium inhalation was undertaken at Forensic Science South Australia over a 25-year period from 1985 to 2009. No cases of helium-related suicides were identified in the first 15 years of the study, with one case between 2000 and 2004 and eight cases between 2005 and 2009. Australian data were also reviewed from 2001 to 2009 that showed 30 cases between January 2001 and June 2005, compared to 79 cases between July 2005 and December 2009, an increase of 163%. A review of Swedish data between 2001 and 2009 showed no cases between January 2001 and June 2005, compared to seven cases between July 2005 and December 2009. Thus, all three areas showed recent and striking increases in cases of suicide involving helium inhalation. Given the availability of helium and the recent promotion of this method of suicide, it is quite possible that this may represent a newly emerging trend in suicide deaths.