In general terms, Right Concentration means establishing the mind rightly. On one level, this can apply to all the factors of the path. You have to start out by setting the mind on Right View. In other words, you use your discernment to gather together all the Dhamma you've heard. Then when you set the mind on Right Resolve, that's also a way of establishing it rightly.

In general terms, Right Concentration means establishing the mind rightly. On one level, this can apply to all the factors of the path. You have to start out by setting the mind on Right View. In other words, you use your discernment to gather together all the Dhamma you've heard. Then when you set the mind on Right Resolve, that's also a way of establishing it rightly. Then you set it on Right Speech, speaking only things that are right.