You use conditional formatting.

Depending on how you calculate your 'due' date, you use a condition like:
=a1+30=today()

Regards
Fred

"lau" wrote in message
...
I want to set a set of criteria for a row, within a give date range, in a
way
that as the 'due' date approaches, the cells change color from green to
yellow to red. how can i set this up?