Abstract: A machine for renting articles, e.g. video cassettes, which stores individual articles in containers (26) from which they may be rented by the user and wherein an opto-electronic emitter and sensor cobination (55) is provided to sense whether an article is in a container when the latter is in its closed state, a further opto-electronic emitter and sensor combination (56) may be provided to sense whether or not a container is in its closed state, a microprocessor (61) is arranged to permit the container to remain in its closed state if the article is sensed in the container and to re-open the container if it is not so sensed, and when the container is closed a predetermined number of further times without the article being sensed, disabling action is taken.