User install software permissions

How do I simply configure the permissions on a Windows 2000 server to allow individuals to install software on their Windows 2000 Pro desktops? All the help and other info I find is for publishing install packages. I do NOT want that. This is a very small office: 15 people. Everyone is trusted and needs to be. Efficiency at their machine is a priority. And I’m lost in the souped-up power and choices of Active Directory. Direct help, or links to tutorials appreciated.