We reviewed and critiqued the conduct and reporting of mediation analyses in 409 studies published in five leading organization studies journals over the past 25 years. The aim of our study was to learn from past practice and to use that knowledge to signal to researchers the importance of correctly applying mediation tests, and to facilitate the valid testing of mediation models and the reporting of mediation results in future studies. We content coded our sample for a wide range of characteristics and found that the majority of inferences of full and partial mediation were based on testing procedures that deviated significantly from procedures recommended by statisticians. In addition, the reporting of results was often incomplete and inefficient. We discussed and evaluated the findings of our study and made recommendations for future testing and reporting of results for mediation models.