When President Gordon B. Hinckley visited Thailand in June 2000, he promised the Saints that one day a temple would be built in Thailand, the announcement that will fulfill that promise was made by President Monson, just a few months short of 15 years later.
The site for the temple was purchased in 2008. At that time the church purchased property on New Petchaburi Road (not far from the Asoke Chapel - Thailand's first - completed in 1972 and dedicated in 1974 by Elder David B. Haight (at that time an assistant to the Quorum of Twelve Apostles).
Church growth in Thailand over the past 18 months has been nothing less than spectacular, with almost 2000 baptisms in 2014, making Thailand one of the top baptizing missions in the church. The offer of a way to have sins forgiven resonated with the Thai people who had suffered from a divided government and many uncertainties since September of 2006. Retention results so far have also exceed the long term average for the country.
It will be interesting to see what countries make up the temple district for the new temple. Clearly Cambodia with 2 stakes in Phnom Penh will be included; but what countries will be left in the Hong Kong district, so that it still has some of its own? Perhaps Viet Nam, Indonesia and Singapore will be left with Hong Kong? While India, Malaysia, Laos and Myanmar are assigned to Thailand.
Since it takes 2-3 years from the time of the groundbreaking to construct a typical new temple, the completion date for the Bangkok Thailand Temple will be 2018 or later, even if ground is broken in the fall of 2015. Groundbreaking cannot be done until the local permits have been obtained, and such permits will require a rendering of the outside of the building, and the specifications for the outside dimensions as well. It is not known if any architectural design work has already been completed or if it is still to be started.