With only a small number of foreign expatriates and high-income earners, emerging economies such as Vietnam and Cambodia were not very enticing for international schools in the past, but that is changing rapidly.
The two countries are among the fastest-growing economies in the world, bolstered by liberalised regulations attracting foreign investors keen to take advantage of young and low-cost workforces.
International schools in such countries tend mainly to serve the children of foreign parents working for multinational companies, embassies and non-government organisations. The number of local children in the international school system has also risen to the extent that they make up the largest single nationality in some countries. However, most schools keep a careful eye on the number of students of each nationality and strive to promote and maintain cultural diversity as their selling point.
At International School Ho Chi Minh City (ISHCMC) in Vietnam's commercial hub, a nationality cap has been set at 25% of the total enrollment. As a result, the school can boast anywhere between 11 and 18 nationalities in each classroom, according to admissions manager Christine Byrne.
The current student body of ISHCMC totals 1,020 and is composed of about 20% Vietnamese children, 19% Koreans, 16% Americans, 8-10% Australians and smaller percentages of other nationalities.
When Asia Focus visited, the school was undertaking summer-holiday renovations, an annual ritual for schools that want to maintain their reputations for high quality. The school has a complete range of facilities for both learning and extracurricular activities including computer rooms, swimming pools, football fields and basketball courts.
Vietnamese students need special permission to attend international schools in their own country. The schools are also required to offer the Vietnamese national curriculum for the Vietnamese students.
Given that demanding regulation, Vietnam has an alternative "bilingual school" sector that caters largely to wealthy Vietnamese. Such schools offer the national curriculum concurrently with the international curriculum, usually in English.
Therefore, international schools such as ISHCMC and British International School, which offer only the international curriculum, are still dominated by the children of expatriates. Another reason is the schools' desire to maintain a broad mixture of nationalities.
In Cambodia, International School of Phnom Penh (ISPP) allows no more than 30% of each nationality. There are 49 nationalities represented among the 737 students, an enrollment that rose 15% from last year and has the potential to reach 1,000 in the next few years. Cambodian children constitute the highest percentage of nationalities, followed by the Americans.
"If everything is stable, the coming years will be a golden age for Cambodia as well as for the international schools market because the economy is booming and business is growing. The country is becoming more attractive to expats," said Barry Sutherland, the director of ISPP.
Today, he said, there are only 12 international schools in Phnom Penh but each has been expanding and the overall number of schools is also expected to grow.
ISPP is building a new campus located 20 minutes by car south of Phnom Penh city, in order to meet the rising demand of both expatriates and the local population. Rising rental rates at the old campus along Norodom Boulevard also pressured the school administrative board to give up the leased property and build the new campus on self-owned land.
The new campus is now serving secondary-level students only and is expected to be completed in August this year. Mr Sutherland said there would certainly be gradual rise in the fees in response to the expansion, but the increases would be managed so as not to shock the parents.
"The school is operated on a not-for-profit basis and the money is going back to the school," he told Asia Focus. "Fees will rise gradually as we grow, because we have to make sure there is enough budget for more staff and for facility maintenance."
The 5.4-hectare campus will be able to accommodate 1,500 students at its full capacity. The new campus has a stadium-sized football field, three basketball courts, a 25x15-metre swimming pool, and an indoor theatre under construction.