Some 170 jobs are to be created at two firms in the Shannon area.
US firm Zagg is to team up with local company Cregg Logistics to manufacture covers for electronic devices and distribute them worldwide.
Richard Bruton, Minister for Jobs, Enterprise and Innovation, said it was a massive vote of confidence in the region and the Irish economy.
"I am developing plans to achieve growth in the economy and to create and protect jobs through reducing costs for business, improving access to finance, and in innovation and R&D," he said.
Zagg, which designs shields and covers for electronic devices such as iPhones, mobiles and laptops, will initially take on 40 staff but added that it expects to create 300 jobs over the next four years.
The company is setting up an international distribution centre at the Shannon Free Zone as part of the joint venture. It will also be home to the expanding sales and marketing, product design and administrative side of Zagg's European business.
Cregg has set up a new division to work alongside the Zagg designers and will create 130 jobs over the next two years. The firm will have sole responsibility for manufacturing, assembly, packaging and logistics of the new venture.
Mr Bruton added: "Today's announcement shows what government and business can do when they work together and shows that there are still many positives in the Irish economy. I will be working hard to ensure that we can build on these positives and get genuine growth going again."
The expansion was secured with the support of the Government and Shannon Development.
Vincent Cunnane, Shannon Development chief executive, said: "This is fantastic boost for Shannon. Both Zagg and Cregg are companies with solid business backgrounds and are prime examples of the type of innovative companies that we are delighted to welcome to the Shannon Free Zone."