Multivariable control design-methods

Hi all, I'm working on control system toolbox. I've obtained a system which is in MIMO form with 2 inputs and 2 outputs. I'd like to decouple the system and design the controller. What are the techniques that are available to perform the same? Will the system become two SISO systems? Is there any relation between the two separate loops? If possible, can you please include matlab code performing the same on a MIMO system?