Shell: Search for two different strings

Hi All,

This could be a really simple one.

I want to search for "String_1" in a text file and when it's found to then search for "String_2" from that point onwards.

What is the best way /command to do this?

Thanks in advance.

Please be more specific.

You're using a terminal like DOS or Bash (Linux) or you want to accomplish that with a programming language?

Sorry,
It's Unix so Bourne, Korn shell or even Perl would do.
Thanks