1. A method for providing an on-demand software execution service comprising the following steps: receiving, from at least one terminal, at least one request for executing at least one software package, by a virtual machine launched on a virtual machine launching server from files of a set of files for launching virtual machines, and selecting, from a set of servers for launching virtual machines, at least one server to which the request will be directed, according to a rule for distributing the execution load of virtual machines by the servers of said set of servers.