In this decade, IRI introduced CoSort as the world's first commercial sort software off the mainframe. CoSort for CP/M 80 and 86 was announced and selling in 1980, followed by PC-DOS in 1981, and MS-DOS in 1982. DOS CoSort version 4.4 was the company's last version for that O/S until it was replaced with a more Windows-oriented package in the mid 1990s. CoSort's command line roots were well established in the 1980's; however, and to this day, many PC users still execute CoSort jobs without its GUI.
CoSort also became the world's first commercial Unix sort package in 1985, developed in C on an AT&T 3B2. Most of IRI's formative revenue came from the growth of commercial Unix. There was no salient competitor in that market until 1993, and IRI has maintained and expanded on CoSort's technological leadership role in Unix sort/merge software ever since.