It’s very controlled beyond prostitutes , helpers (maids) and labourers. They even specify which race and sex can do which job . Construction bangledesh (and some others) under 60. You must employ 1 local at 1400 a month to employ 7 Bangladeshi with no minimum wage and house them 24 to a room in what they call a dormitory , some might call a labour camp where COVID was out of control.

Helper , female under 50 https://www.mom.gov.sg/passes-and-permits/work-permit-for-fo... sourced from certain country’s only , At the professional and executive level it has been capped at about 200k and lowering for the last 10 years (out of about 6mil )