Address binding of instructions and data to memory addresses can happen at three different stages
Compile time: If memory location known a priori, absolute code can be generated; must recompile code if starting location changes.
Load time: Must generate relocatable code if memory location is not known at compile time.
Execution time: Binding delayed until run time if the process can be moved during its execution from one memory segment to another. Need hardware support for address maps (e.g., base and limit registers).