This is a great introduction to Stoicism for the modern world. The author takes quite a few of the concepts and updates them through a 21st century philosophic viewpoint (mainly through the use of more rigorous logic behind the scenes).

The best update comes with how one should deal with things one can and cannot effect. He updates this from two to three: things you have no effect on whatsoever, things you have some effect on, and things you have total control of. Earthquakes are one on example of the first - no idea of when they are coming and one just has to do her best to deal with it. The second involves dealing with other people: one can control what one says and does to another, but no control over how that person reacts. Third, one has control over oneself.

There are a few ideas in there that I think don't pass modern studies of sociology/psychology - the chapter on relationships , in particular - but otherwise a very compelling read.