The market is home to more than 600 million people, almost double the population of the United States. The combined economy will be the seventh largest in the world, comparable to that of Britain or Brazil.
Language skills will matter in the new single market, especially in English, the only lingua franca in Asean.
"English will be extremely important as a means for communications in business," said Treenuch Phaichayonvichit of the Thailand Development Research Institute. "However, Thai students seems to perform poorly. The mean score on national tests in English has always been below 50, which is a failing grade by any standard.