| Imperial Service Order | |
|---|---|
 Decoration as worn by gentlemen. | |
| Awarded by Charles III | |
| Type | Order |
| Established | August 1902 |
| Awarded for | Nationally important service |
| Status | Currently constituted (only in Papua New Guinea) |
| Sovereign | Charles III |
| Grades | Companion |
| Post-nominals | ISO |
 Ribbon bar of the order | |
The Imperial Service Order was established by King Edward VII in August 1902. It was awarded on retirement to the administration and clerical staff of the Civil Service throughout the British Empire for long and meritorious service.[1] Normally a person must have served for 25 years to become eligible, but this might be shortened to 16 years for those serving in unhealthy climates abroad. There is one class: Companion. Both men and women are eligible, and recipients of this order are entitled to use the post-nominal letters 'ISO'.[2][3]
- ^ "National Archives". Archived from the original on 5 March 2012. Retrieved 26 November 2009.
- ^ Duckers, Peter (2004). British Orders and Decorations. Shire Books. pp. 48–51.
- ^ Honours and Titles (second ed.). HMSO. 1996. p. 101.