How do you know the battery is good?
Does the engine turn over?
Can any sounds be heard when attempting to crank?
Any prior work done on the vehicle which could lead to this occurrence?
Have you checked all fuses? With a test light on both poles of the fuses and a visual check.
Check tightness and contact of battery terminals.
Check to see if you have power on the main (big) terminal on the start solenoid and power at the start signal terminal (small) when key is switched to "start". Starter is located on the left side of the motor.
Possible battery, igntion switch, EWS or starter motor issue.