The Building Safety Act 2022 (BSA 2022) paved the way for significant changes to the law on building safety. For general information on the reforms introduced by BSA 2022 and its key provisions, see Practice Note: Building Safety Act 2022—key provisions and issues. BSA 2022, Pts 3 and 4 provided the framework for a new regulatory system applicable to ‘higher-risk buildings’ (HRBs). Through amendments to the Building Act 1984 (BA 1984), BSA 2022, Pt 3 enabled the creation of a stringent building control regime applicable to the design and construction of works to HRBs. The requirements of this regime were set out in a package of secondary legislation laid in August 2023, and which came into force on 1 October 2023. BSA 2022, Pt 4 imposes extensive risk management and reporting obligations on those responsible for occupied HRBs. These measures are referred to, collectively, as the HRB regime. This Practice Note considers which types of buildings and associated works are ‘in scope’ of the HRB regime, by reference to the definitions, criteria