After your Windows 2000 network design has been deployed and is fully operational, your test lab serves as an excellent change control and integration test facility. All proposed changes to your production environment can be rigorously tested in the lab before deployment to minimize their risks and associated expense. Of course, keeping your entire lab might be difficult, as many managers will find it hard to accept the equipment depreciation in their budget. Most will want to put the equipment back in production. You can try to fight this by demonstrating that the cost savings for future deployments will outweigh the losses due to depreciation. Even if you lose that battle, a scaled-down version of your lab should be kept operational.