Abstract: A method and system for controlling mutually exclusive resources and for preventing deadlocks in a multi-tasking computer system by generating a graph containing nodes to which are mapped the tasks included in a flow of processes and the critical resources which may be appropriated by at least one of the tasks. The nodes of tasks executed sequentially are arranged sequentially; the nodes of tasks executed in parallel are arranged in parallel with each other and each node of a critical resource is arranged in parallel with every node which may appropriate it. Every time a signal to being execution of a task is transmitted, a token is generated in the task node and the critical resource node is parallel with the task node.