The Conference decision by which a Convention in force is found to be obsolete and is removed from the body of standards. As a result, all legal effects arising out of the Convention in question between the Organization and its Members are definitively eliminated, namely States having ratified that Convention are no longer required to submit reports under article 22 of the Constitution, and may no longer be subject to representations (article 24) or complaints (article 26) for non-observance; ILO supervisory bodies are not required to examine its implementation; and the Office ceases all relevant activities, including the publication of the text of the Convention and the official information regarding its ratification status. However, the abrogation of a Convention does not affect any national legislation that has been adopted with a view to giving it effect, nor does it prevent a State from continuing to apply a Convention if it so wishes.

Following the entry into force in October 2015 of the 1997 constitutional amendment, the Conference is empowered, by two-thirds majority and upon recommendation by the Governing Body, to abrogate a Convention in force if it appears that it has lost its purpose or that it no longer makes a useful contribution to attaining the objectives of the Organization (article 19(9) of the Constitution). The term ‘abrogation’ refers to Conventions which are in force whereas the term ‘withdrawal’ is used for Conventions which have never entered into force or are no longer in force due to denunciations, and to Recommendations. Abrogation and withdrawal follow the same procedure set out in article 45bis of the Conference Standing Orders. The only difference is that the Conference was empowered, on the basis of its Standing Orders, to withdraw an instrument even before the entry into force of the 1997 constitutional amendment.

In accordance with article 45bis of the Conference Standing Orders, when an item on abrogation or withdrawal is placed on the agenda of the Conference the Office must communicate to the governments of all member States not later than 18 months before the opening of the session of the Conference at which the item is to be discussed, a short report and questionnaire requesting them to indicate within a period of 12 months their position on the subject of the said abrogation or withdrawal. On the basis of the replies received, the Office draws up a report containing a final proposal which is distributed to governments four months before the opening of the Conference.

As at September 2019, the Conference had abrogated ten Conventions, including Conventions Nos 4 and 41 prohibiting the nigh work of women in industry, Convention No 15 setting a minimum age for trimmers and stockers and Conventions Nos 50, 64, 65, 86 and 104 concerning the recruitment of indigenous workers in dependent territories. All these Conventions were found to have had lost their purpose with regard to the Organization, either because they have been replaced by more modern instruments or because they no longer reflect current practices and conceptions.