In 1948, the Emergency was declared in Malaya. Walker's immediate role was to train and equip the irregular Ferret Force. In late 1948 he was appointed Commandant of the Far East Land Forces Training Centre in Johore Bahru with the task of training British units, arriving from UK, in jungle fighting. It later became the Jungle Warfare School at Kota Tinggi. He was appointed OBE for his work on Jungle warfare training. He also highlighted the many deficiencies in equipment and neglect of the lessons learned in Burma. He then had his first posting to UK as a student at the Joint Services Staff College. In 1950 he was appointed to command 1/6 Gurkha Rifles. Walker created a very effective jungle fighting battalion with many notable successes, including killing high ranking communists, in the three years he was in command.