The Irritrol Web site doesn't list Windows Vista in the system requirements. However, often programs will run on both operating systems as their underlying foundation isn't much different. Have you actually tried installing and using the software on Vista? Occasionally you'll encounter a program that will fail during the install process saying that it is incompatible with your operating system but this is rare. I say give it a shot if you haven't already. If you have tried to install it and it doesn't work or won't install please give us the details. I'm sure there's a way to work around it.