On May 24, 2011, at 12:48 PM, Nathaniel Flath wrote:

How does emacs decide when to split an existing window and when to
make a new window? I prefer having four windows side-by-side, but when
I run "other-window" type commands, emacs tends to split until I have
eight windows (two rows of four) before it starts reusing windows. 

Take a look at split-width-threshold and split-height-threshold

My preferences don't match yours so I can't suggest how to set them.