Retired General Surayud Chulanont has begun work as Thailand's new military-appointed prime minister, after being sworn in on Sunday.
Gen Surayud was blessed by the nation's top Buddhist monk, before moving into his office in Government House.
His first major task will be to appoint a Cabinet, which he is expected to have done by the end of this week.
The tanks which have been on the streets of Bangkok since the 19 September coup have now been withdrawn.
Pridiyathorn Devakula, the head of Thailand's central bank, told reporters he had agreed to join the Cabinet, but that his exact job had not been confirmed.
As well as announcing the new prime minister on Sunday, the military generals that led the coup also unveiled an interim constitution.
This details the process of drafting a new long-term constitution, and promises democratic elections in October 2007.
Gen Surayud was sworn in as the country's 24th prime minister during a short ceremony in Bangkok on Sunday afternoon.
He said his government would focus on "people's happiness" above economic growth.
"The king has appointed him to administer the country from now on," coup leader Sondhi Boonyaratkalin said during the ceremony at Government House.
Tanks have left Bangkok now the new PM is in charge
Gen Surayud has previously spoken out against military involvement in politics, but he told reporters he felt he had to take the job "because of the necessity to address the country's problems".
He said he would try to tackle political divisions and end an Islamic insurgency in the country's south.
"I will put these two issues at the top of my agenda," he said. "I will make a great effort to solve these two problems within one year."
Gen Surayud wore a white uniform for the ceremony and prostrated himself in front of a giant portrait of King Bhumibol as a sign of respect. He stood alongside six of the leading officers behind the coup.
Gen Sondhi was quoted by Reuters news agency as saying he visited Gen Surayud on 28 September "and spent half an hour convincing him to take the job while the country is in crisis".
Gen Surayud is an army veteran, and one of the few senior Thai figures who is respected by military and civilian leaders alike.
By choosing him as prime minister, the military may hope to allay international fears over the coup.