Bringing a window to the front

[Gorshkov <listsubscriptions oghma on ca>]

I have an application where I occasionally open a window when a user 
selects a field in another window. 2nd window (usually) is kept open, 
but over time becomes hidden by other windows.

The second window automatically becomes the active window when I first 
show it, so that's not a problem. My question is this: How do I force 
the 2nd window to become the active window, if it is already visible?