All unfair dismissal complaints and complaints of sex, race and disability discrimination, plus most other complaints, made to Employment Tribunals are automatically referred to ACAS.

ACAS appoints a conciliation officer in every such case. He will approach the parties to assist them to resolve their differences without the need for a Tribunal hearing (see CONCILIATION OFFICERS/functions of , which includes a list of the types of complaint which tribunals must notify to ACAS). Redundancy problems, which have technically been outside the remit of ACAS, were added as from 1st October 1998 (see Redundancy/ACAS and conciliation officers ).

The traditional (and still valid) way for employers and employees to ensure full legal effectiveness of an agreed settlement of most cases in which Tribunals have jurisdiction is to ensure that the settlement is reached with the involvement of an ACAS conciliation officer, and preferably is recorded on the standard ACAS settlement form COT 3.

A compromise agreements procedure to enable employers and employees to make fully binding settlements of disputes without ACAS involvement was introduced in 1993.

See also notes at Unfair dismissal/compromise agreements and/or at Procedure of Employment Tribunals/2004 rules/background, general and amendments .