| In force components |
| Number | Title | Status |
| X.501 (10/19) | Information technology - Open Systems Interconnection - The Directory: Models | In force |
| X.501 (2019) Amendment 2 (10/24) | Miscellaneous enhancements | In force |
| X.501 (2019) Amendment 1 (10/21) | Information Technology - Open systems Interconnection - The Directory - Models - Amendment 1: Miscellaneous enhancements | In force |
| |
| Superseded and Withdrawn components |
| Number | Title | Status |
| X.501 (11/88) | The Directory - Models | Superseded |
| X.501 (11/93) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (08/97) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (1997) Technical Cor. 1 (03/00) | | Superseded |
| X.501 (1997) Amendment 1 (03/00) | Enhancements for the support of ITU-T Recommendation F.510 and mapping of directory protocols onto TCP/IP Never published, consolidated in ITU-T X.501 (02/2001). Only the electronic prepublished version is available on ITU Website | Superseded |
| X.501 (1997) Technical Cor. 2 (02/01) | | Superseded |
| X.501 (1997) Corrigendum 3 (05/05) | | Superseded |
| X.501 (02/01) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (2001) Corrigendum 1 (05/05) | | Superseded |
| X.501 (2001) Corrigendum 2 (11/05) | | Superseded |
| X.501 (2001) Corrigendum 3 (05/08) | | Superseded |
| X.501 (08/05) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (2005) Erratum 1 (08/06) | Applies to English version only | Superseded |
| X.501 (2005) Corrigendum 1 (05/08) | | Superseded |
| X.501 (2005) Corrigendum 2 (11/08) | | Superseded |
| X.501 (2005) Corrigendum 3 (02/11) | | Superseded |
| X.501 (2005) Corrigendum 4 (04/12) | | Superseded |
| X.501 (11/08) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (2008) Corrigendum 1 (02/11) | | Superseded |
| X.501 (2008) Corrigendum 2 (04/12) | | Superseded |
| X.501 (2008) Corrigendum 3 (10/12) | | Superseded |
| X.501 (10/12) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
| X.501 (10/16) | Information technology - Open Systems Interconnection - The Directory: Models | Superseded |
