you can remove or delete the objects in the same way using the actionscript in Flex or Flash Builder as you do in the flash. Deleted or Unloaded objects are automatically detected by garbage collector and removed from the memory when the garbage collection begins after certain intervals. So there generally there is no immediate freeing of memory noticed. Garbage collection is entirely managed by flash player and works according to need. Garbage collector may not run or free your memory if your system have enough memory and is not required by any other program.