"Why Did You Leave...?"
It is probably inevitable that an interviewer will ask about your previous employment, and, more specifically, why you no longer work there. Even if you weren't fired from that job, this is a difficult question to negotiate. To help you form an acceptable answer to this query, use the acronym CLAMPS:
C=Challenge -- You weren't able to grow professionally in that position.
L=Location -- The commute was unreasonably long and/or arduous.
A=Advancement -- There was nowhere to go. You had the talent, but there were too many people ahead of you.
M=Money -- You were underpaid for your skills and contributions.
P=Prestige -- You wanted to be with a better organization.
S=Security -- The organization was not financially stable.
The value of the CLAMPS system is that it allows you to always display some form of loyalty to your former employer. You should never express any form of hostility or ill will toward your previous boss. You will almost never get the job if you don't seem like a team player and a respectful employee, one who does not undermine his or her employer's authority.