Second Interview
Now that you've had a chance to meet some of the people and have researched some of the organizational goals, this follow up should be more relaxed, but don't get too comfy. Ask someone you are in contact with for an agenda describing what to expect. Review more questions for the second interview but be prepared to answer questions on how you "feel" about things, such as working there or the type of work.
Meeting Staff
In the first round, you likely met with the human resource staff or staff level members of a division, this time you'll likely be meeting the hiring manager or staff members not involve in the first interview. Feeling the pressure? Consider what you wear, you'll still need to make a good first impression on some people.
Make The Right Impression
Relax a little, once you've made it to this point, you've passed the qualification tests, now it's time to see if you're suitable and compatible; a good fit. Be yourself, but mind the impression you're giving off.
Determine what impression you want to leave

Do you want to be seen as confident, capable, compatible, and a great communicator?
Colleague Interview
Sometimes and interviewer may be so impressed with you that they will immediately call a colleague in to meet you. Don't worry, stand up, shake their hand and relax. The colleague is responsible for directing the meeting from here. They may ask questions that you've already answered. They will probably lean toward personal questions that are given on your application and resume. They may ask about your motivation to work here at Company X. Again, your goal is to be likeable and a good fit.
Delayed Second Interview
If you have time between your first and second interview, reflect on your conversation. What were some of the themes your remember the interviewers talking about? Certainly go back to the research phase and look at the details of the position. You may have already asked questions of the interviewer, so formulate some new ones. Think about your salary and compensation requirements, how will you answer questions about that?
Be prepared for the next time, this Ultimate Guide to Job is an excellent resource for all aspects of the job interview.