In 1970 the Institute formed a Working Party to formulate views on the revision of the collision regulations. Its Interim Report is published in the Journal for October 1970 and two further contributions, by Calvert and García-Frías, were published in a subsequent number (24, 413–20). The Interim Report referred to the value that a manœuvring diagram along the lines originally proposed by Calvert and Hollingdale would have in helping the mariner to assess the effects of collision situations on alterations of course and speed. It has not been possible to secure unanimity about the form of this diagram, but the one illustrated below is based on the contributions of several members and has met with the approval of the majority of the Working Party.