concentration vs mindfulness

Check out this link, that asserts concentration is not mindfulness.

One pointed is an aspect of mindfulness, and concentration is it's near cousin, so is absorption, but for me mindfulness has a quality of kind, non-judgemental observation, that leads to continuity of purpose and skillful behavior and speech, among other things. I don't know who this Theravadan teacher Ajahn Sumedho is, but he's got a book.

There's truly an ocean of Dharma. Do I need more? I need to put in place what I already have.