Officials at oil company BP say the latest attempt to stop the leak that has been pouring into the sea off the coast of America is working.
They've used underwater robots to put a mile long tube into the broken pipe to send some of the oil to special ships on the surface of the ocean.
The next part of the plan is to try and stuff lots of mud into the pipe to stop the flow of oil completely.
But lots of people are worried about the effects the oil will have on land.
A top American coast guard has warned it could reach the southern Florida coastline.
And environmental charity Greenpeace say oil seems to be washing up in Louisiana.
A worker for charity Greenpeace shows oil by the Mississippi River.
American President Barack Obama has set up a group of experts to look into what's going on.
And BP says it won't complain after being told it will have to pay for all the damage caused by the spill.