As HMRC moves towards a fully digital tax system, the capability of its IT systems, including in terms of cyber security, will become increasingly important to HMRC’s ability to operate effectively. HMRC has recognised that, due to the need in the past to forgo operational maintenance and upgrades to its systems to secure cost savings, its IT systems now constitute a significant risk to the Department.58 We asked HMRC about the impact of the relatively poor state of its IT infrastructure on the cost-effectiveness of its administration of the tax system. HMRC told us that it is important that it has sufficient investment to modernise its IT estate as well as continue to maintain its legacy systems to ensure they are kept up to date and are safe from cyber-attacks and catastrophic losses. In the case of its legacy systems, ‘patching’ is a never-ending process.59