Information Technology: IRS Needs to Complete Modernization Plans and Fully Address Cloud Computing Requirements, GAO-23-104719 Published: Jan 12, 2023. Publicly Released: Feb 07, 2023. “The Internal Revenue Service’s (IRS) legacy IT environment includes applications, software, and hardware, which are outdated but still critical to day-to-day operations. Specifically, GAO’s analysis showed that about 33 percent of the applications, 23 percent of the software instances in use, and 8 percent of hardware assets were considered legacy. This includes applications ranging from 25 to 64 years in age, as well as software up to 15 versions behind the current version. As GAO has previously noted, and IRS has acknowledged, these legacy assets will continue to contribute to security risks, unmet mission needs, staffing issues, and increased costs. Modernization best practices call for documenting plans that include three key elements: milestones, work to be performed, and disposition of legacy systems. As of August 2022, IRS had documented plans for the 21 modernization initiatives that were underway, including nine associated with legacy systems. All 21 plans addressed two key elements. However, the plans for six of the nine initiatives did not address the disposition of legacy systems (see table). Officials stated they would address this key element at the appropriate time in the initiatives’ lifecycle; however, they did not identify time frames for doing so.”