The recommendations were put into practice under Harold Macmillan during a successful experiment from 18 July 1961 to the end of the session ( 4 August ) , and the sessions were made permanent in the following session , with the first of these on 24 October 1961 .
The recommendations were put into practice under Harold Macmillan during a successful experiment from 18 July 1961 to the end of the session ( 4 August ) . 
 PMQs were made permanent in the following parliamentary session , with the first of these on 24 October 1961 .