windows batch file: calling executable in another directory

This seems like something simple, but I don't seem to be able to get it. I have a directory called "test" with an executable hello.exe that basically prints "hello" onto the screen.

I want to execute this program from the current directory using relative paths. So I write

test\hello.exe

Thinking it would execute the program "hello.exe" located in directory "test". But it doesn't. Am I missing something?