Abstract: A method provides isolated and secured execution environments on a terminal controlled by one or more processors having one or more processor cores. The processors execute a first trusted execution environment and a second legacy execution environment. At least one trusted application (4) is executed in the trusted execution environment and processes sensitive data, and a legacy application (2) is executed in the legacy execution environment. Execution environments, called sanctuary instances, are isolated from the first and second execution environments and are executed on a dedicated processor or dedicated processor core. The sanctuary instances may be present physically or virtually. Sanctuary memory areas are assigned to the respective processors or processor cores. At least one sanctuary application (10) is executed in a sanctuary instance, and a sanctuary application (10) interacts with one or more legacy applications (2) and with one or more trusted applications via at least one communication channel.