By 1960, a number of forces were to shape the direction of the company, the publication list and its graphic design. On 20 April 1961, Penguin became a publicly listed company on the London Stock Exchange; consequently, Allen Lane had a diminished role at the firm though he was to continue as Managing Director. New techniques such as phototypesetting and offset-litho printing were to replace hot metal and letterpress printing, dramatically reducing cost and permitting the printing of images and text on the same paper stock, thus paving the way for the introduction of photography and novel approaches to graphic design on paperback covers. In May 1960, Tony Godwin was appointed as editorial adviser, rapidly rising to Chief Editor from which position he sought to broaden the range of Penguin's list and keep up with new developments in graphic design. To this end, he hired Germano Facetti in January 1961, who was to decisively alter the appearance of the Penguin brand. Beginning with the crime series, Facetti canvassed the opinion of a number of designers including Romek Marber for a new look to the Penguin cover. It was Marber's suggestion of what came to be called the Marber grid along with the retention of traditional Penguin colour-coding that was to replace the previous three horizontal bars design and set the pattern for the design of the company's paperbacks for the next twenty years. Facetti rolled out the new treatment across the Penguin line starting with crime, the orange fiction series, then Pelicans, Penguin Modern Classics, Penguin Specials, and Penguin Classics, giving an overall visual unity to the company's list. A somewhat different approach was taken to the Peregrine, Penguin Poets, Penguin Modern Poets, and Penguin Plays series. There were over a hundred different series published in total.