Hundreds of jobs to be created
Several hundred jobs are being created with two separate announcements.
German multi-national software firm SAP is to lead the investments with an expansion of its operations in Dublin and Galway.
About 250 positions are to be created in sales and services and at its cloud computing and support centre.
Elsewhere, a casino and private members club is to open in Swords, north Dublin, creating 50 jobs. KaiRo International plans to increase the workforce to 70 over the next six months with a training centre set up for croupiers.
Taoiseach Enda Kenny said the expansion at SAP has contributed to Ireland's growing reputation as a global hub for the digital industry.
Some 150 jobs will be created over the next three years within its services, sales and global support functions at Citywest in Dublin, with 100 posts at its newly-created cloud services and support centre in Galway. Both projects are supported by the Irish Government through IDA Ireland.
Mr Kenny said: "SAP is the largest software company in Europe and the third largest software company in the world and its decision to further expand its Irish operations demonstrates the real value of an economically stable business environment and Ireland's position in Europe when it comes to attracting the overseas operations of major technology companies like SAP.
"I wish SAP every success with both these expansions and offer the continued support of the Irish Government into the future."
SAP Ireland was established in 1997 and already employs 1,200 people between its two sites. Liam Ryan, managing director, said Ireland has provided a highly-skilled and innovative workforce.
"Today's announcement is all about gearing SAP up for the company's next wave of technology innovation to meet business needs in the areas of cloud computing, mobile applications and high-performing database technology," he said.