The most successful behaviour-liars are those who, instead of consciously concentrating on modifying specific signals, think themselves into the basic mood they wish to convey and then let the small details take care of themselves. This method is frequently used with great success by professional liars, such as actors and actresses. Their entire working lives are spent performing behavioural lies, a process which can sometimes be extremely damaging to their private lives. Politicians and diplomats are also required to perform an undue amount of behavioural lying, but unlike the actors they are not socially 'licensed to lie', and the resultant guilt feelings tend to interfere with their performances. Also, unlike the actors, they do not undergo prolonged training courses.