The primary thing for me is being in the right role & working for the right people. Stress is pretty low when you are doing something you do very well & tend to enjoy with people who support you.

That's not to say low stress equates to only doing easy things. I work for a consulting company so there is a lot of change involved as I shift from client site to client site; some projects have tight & sometimes unrealistic deadlines requiring extra hours and more intense effort, while other projects can introduce more soft, people related issues. But at the end of the day I am confident I can do the work required and have people within my own company who have my back if there is anything I can't handle.

And, for me, an aspect of this also does come down to the issue of confidence. I used to get a little stressed when starting on a new project with a new client due to the amount of unknowns involved. However, I've learned to relax about this; understanding that my track record has proven that I have the skills necessary to be effective and successful when I hit the ground even without knowing what exactly will be involved.