There are many common questions which you are likely to see when interviewing for a job and this is one of them. While this question may at first appear to be fairly black and white, the most important thing to understand is that it is not what it appears. An effective answer to this question should not be one or the other. Keep in mind that regardless of the type of job for which you are interviewing, most positions require effective workers to be a bit of both to different degrees. Even if you are interviewing for an entry-level position you will still need to have some ability to act as a team leader. The same is also true if you are applying for a management position. Not only will you need to be able to act as a reliable and effective team leader, but you will also need to be a team player as well.
Therefore, when the interviewer asks this question they are not simply looking for an answer that indicates you are one or the other. They are instead looking for evidence that you are able to act as both as the situation calls for it.
In responding to this question you should also give some thought to the particular question for which you are interviewing. Think about the types of duties that are likely to be associated with that job. Think back on the job posting and what was described relating to the job.
It is also a good idea to given an example of how you are able to work as team player or a leader when possible. For example, you might indicate that you like the idea of working in teams because it is easier for people to share ideas, work together and ultimately arrive at better decisions when working in teams. Of course, at the same time, you should follow-up with an indication that you are at ease working independently as well. The same would also be true if you sense that the position in question would require someone to primarily act as a team leader. In that situation, you might say that you work well independently due to the fact that you are self-motivated, conscientious and organized. Along the same lines, you are also comfortable working in teams and understand that in some situations the team approach is the best.