There is provided a method of protecting the execution of a software application, the method performed by a plurality of processes comprising a process for executing the software application and a plurality of protection processes, wherein each protection process in the plurality of protection processes is configured to: monitor a process state of at least one other process in the plurality of processes to determine whether said process state corresponds to a predetermined process state; and perform a predetermined action in response to a determination that said process state corresponds to the predetermined process state; wherein the plurality of protection processes are configured such that a process state of the process for executing the software application is monitored by at least one protection process and a process state of each protection process is monitored by at least one other protection process in the plurality of protection processes. Additionally provided is a computer program and a system for carrying out the method and a computer readable medium for storing such a computer program.