Ion Storm Inc. (sometimes spelled ION Storm) was a video game development company founded 1996 in Dallas, Texas. In 1997, Warren Spector founded the company's Austin branch, which would develop the first Deus Ex game and later Deus Ex: Invisible War.
Due to financial troubles, the company's Dallas branch closed in 2001, leaving the Austin branch as its headquarters, which in turn would also close in 2005, dissolving the company. Eidos Interactive, which had acquired 51% of the company in 1999 and published its Deus Ex titles, inherited the intellectual property.