Vodafone has launched 5G services in parts of five Irish cities, making it the first Irish mobile operator to offer the high-speed service commercially.
5G is the next generation of mobile data connectivity, capable of considerably faster downloads than existing 4G and 3G technology.
It can also handle larger volumes of data, which is seen as increasingly important as more internet-connected devices come to market.
From today, Vodafone's 5G network will be available in parts of Cork, Dublin, Galway, Limerick and Waterford, with the operator promising to extend to further locations "over the coming months".
However, most customers in those areas will struggle initially to avail of the faster speeds, as few devices are capable of connecting over 5G.
Vodafone said it would begin selling one 5G-capable smartphone from tomorrow, with a second device going on sale at the end of the month.
"5G is set to revolutionise how we use and adopt technology and will have a huge impact on businesses and society in Ireland," said Vodafone Ireland CEO Anne O'Leary.
"It will bring high speed, ultra-low latency and highly secure connectivity to a massive amount of devices; and is a technology that will unlock a vast array of new use cases through Vodafone's next-generation network."
Vodafone's rollout in Ireland follows the launch of 5G services in the US in April, with some British cities also seeing upgrades in recent weeks.