Two bodies established by the Government assumed new responsibilities today.
Irish Water took over the statutory responsibility for the provision of water and waste water services from the country's local authorities.
The transfer came ahead of the introduction of water charges in October, with householders set to receive their first water bills in January 2015.
A new State body dedicated to child protection and family support, the Child and Family Agency, also officially entered service this morning.
The agency involves the bringing together of over 4,000 staff and a budget of almost €600m from three existing bodies - the Health Service Executive, the Family Support Agency and the National Educational Welfare Board.