how to get lines prior to the line being searched

Hi,
Can anbody please let me know how i can retrieve lines above the line being searched in a file.
I am looking for an error message from a file, if I see that message I want the lines above that message along with this line.
how do we do this.
Please do let me know

An example which i have put here is below
System state dump is made for local instance
System State dumped to trace file /u01/app/oracle/admin/prod/bdump/prod1_diag_12767.trc
Fri Oct 3 14:47:34 2008
Trace dumping is performing id=[cdmp_20081003144734]
Fri Oct 3 14:47:34 2008
Instance terminated by PMON, pid = 12765

I am looking for the line "Instance terminated" in my script
if I recieve i want to grep lines above the searched message along with the searched message

Please do let me know

Thanks in advance

Check grep's -B flag.

thank you very much that does the trick.