Business process to be mapped

Hi SAP gurus,

I want to map a business process in SAP which is described below:

1) I have a manufacturing Plant where currently my manufacturing processes are running.

2) Now a new requirement has come where another company will supply his raw materials to my plant and on his behalf I will create his finished products using those raw materials supplied. Finally I will send him back those finished products.

That means it will be a subcontractor's role for my plant.

How to map this scenario in SAP.

Plz. Help.

Regards,

Brahm