by the 1920s, printing had become the biggest industry in watford. the biggest printers in the town were sun printers ltd and odhams press. watford was the biggest printing centre in the world and many advances in printing were made in watford. during world war ii the prints were taken over by the government who used them to print propaganda. after the war, the printing industry began going into decline. union activity was common in watford and advances in technology meant much of the industry became obsolete. odhams press closed down in 1978 and the sun moved out of watford during the 1980s after market reforms allowed it to do so.