Partition Question - Making 1 bigger, the other smaller

[ergonomics]

So i've got one hard drive that's partitioned. But i'm running out of space on one partition, and i want to make it bigger by taking the space off the other drive.

Is this possible? If so, how? Will i have to format? Can it be done in the BIOS or with DOS or will i need something like partition magic or something?

Appreciated!