With just days to go before Qatar hosts the World Cup, rights groups fear that a window for addressing the widespread exploitation of foreign workers could soon close.

The long run-up to this month’s World Cup has brought unprecedented scrutiny to the treatment of the millions of foreign workers in the Gulf Arab nation who built stadiums and other infrastructure, and who will staff hotels and sweep the streets during the world’s biggest sporting event.

In the face of heavy international criticism, Qatar has enacted a raft of reforms in recent years, including the partial dismantling of a system that tied workers to their employers and enacting a minimum wage — changes praised by the U.N. as well as rights groups.

But activists say abuses ranging from unpaid wages to harsh working conditions in one of the hottest countries on Earth, are still widespread, and that workers — who are barred from forming unions or striking — have few realistic avenues to pursue justice.

They also worry about what happens after the monthlong tournament ends in December, when the international spotlight moves on and employers slash their payrolls.

Qatar says it leads the region in labor reforms and that progress will continue after the World Cup. Officials from the ruling emir on down have lashed out at critics, accusing them of ignoring the reforms and unfairly singling out the first Arab or Muslim nation to host the Cup.