After college and divinity school, Achor worked as a freshman proctor and teaching assistant at Harvard University.

The company consists of researchers, speakers, and trainers who offer positive psychology-related services to improve work performance.

[7] This book features research that Achor conducted with Ali Crum and Prof. Peter Salovey at Yale University at the large Swiss bank UBS, which was published in The Journal of Personality and Social Psychology, and provided evidence that changing one's mindset about stress changes the physical effects of stress.

[9] Achor also frequently writes for the Harvard Business Review, with more than thirty five articles in both the online and print versions of the journal.

Poor Ash's Almanack [16] states "My much bigger disagreement is with Achor’s anti-defensive-pessimism stance: for all the good that Before Happiness did me (and believe me, it was a lot), abandoning defensive pessimism was a painful and emotionally damaging mistake.