It doesn't make sense for your company to do some jobs on its own. Even when the job isn't too big, it may just be that you don't have the expertise or equipment to do it. When that happens, you need to use Procurement Management to find another company to do the work for you. If you find the right seller, choose the right kind of relationship, and make sure that the goals of the contract are met, you'll get the job done, and your project will be a success.
The procurement management processes are: