That depends upon the situation and your specific requirements. Many penetration testing engagements can be conducted remotely via the Internet, whether that be by direct access, or via VPN or VM/device shipped to your network. Remote testing does have the advantage of reducing travel costs and expenses. In some circumstances however, it may not be possible, or desirable to provide remote access to the environment, so an onsite visit may be required. Additionally, some of our clients prefer our testers to complete some or all testing onsite, so they can more easily interact during the process. Options will be discussed during the scoping exercise to find the best solution for your project.