It is up to you to decide who does the actual installation. Proper installation is crucial to window performance, so at Pella, we offer a couple of options for installation, including working with your local showroom or directly working with a Pella Certified Contractor who is well-versed in all things Pella windows. You also have the option to hire an independent contractor locally or do it yourself! We will discuss this while meeting with you about your replacement windows project.