The Government was sharply criticised at the conference for its "failure" to adequately resource the labour inspectorate of the Department of Enterprise, Trade and Employment.
CPSU president Betty Tyrrell-Collard said a lack of resources was preventing the inspectorate from carrying out its important role in ensuring there was full compliance with employment legislation such as the minimum wage.
"Law, whether it's criminal law, labour law or whatever, is no use unless it's enforced, and there are simply too few inspectors to do the job properly," she said.
The State has 21 labour inspectors, although this is expected to increase when a review of employment rights legislation and enforcement, set up under Sustaining Progress, is completed.
As reported in The Irish Times yesterday, inspectors have told the Government in a document prepared as part of that review that they are understaffed and lack other supports such as adequate training and in-house legal back-up.
Ms Tyrrell-Collard said it should be a central objective of the Irish Congress of Trade Unions in the negotiations for any future national wage agreement that a fully resourced labour inspectorate be established.
She also called for a radical overhaul of the work permit system to help "end the exploitation of migrant workers and the scandalous practices of certain unscrupulous employers".
Work permits should be held by workers themselves, rather than by employers, as is the case at present, she said.
The department says a number of protections for migrant workers will be enshrined in the Employment Permits Bill, to be published during the next Dáil session.