Interviews are a glimpse at what you have to offer – more importantly, they are glimpse at what the company you are meeting with has to offer.
Come to interviews armed with good questions. Ask why the interviewer joined the company and why they have stayed; ask what turnover is like; ask about potential growth opportunities in the company.
Demonstrating before you are hired that you are interested in staying for the long haul can be as easy as asking a good question or two to your interviewer.