Expats in Singapore

We are working with a company that runs international schools in Singapore. In order to figure out what extra capacity they need to build for the coming academic year, we are helping them understand what demand changes (if any) there will be within the expat population in Singapore. In connection with that, we would like to speak to HR departments and/or other executive officials of global firms that have branches in Singapore and employ expatriates, in particular North Americans, British, Australians, and Koreans. We would like to find out what their short-term hiring and expat relocation plans are, i.e. whether they expect a decrease in expat inflow on account of the recent economic downturn and how long it is going to last. Any contacts that you could direct me to at MNCs in Singapore would be very helpful