I think I must be reading the documentation incorrectly ... I read that the jUnit dir attribute is the directory to run the vm from? That is to say, the directory I would be in to run the class? My jUnit task looks like this: I compile to an installation dir which is c:/install/site/classes. ${classes.dir} is set to: The ant build file is in a config directory outside the java directory structure. When (using a console) I go to that directory and run the test by hand, it works just fine. But I get a ClassNotFoundException when I run it through Ant. I have read most of the documentation on    More>>