The computational methods to find the transition states (TSs) are powerful to understand the mechanisms of organometallic reactions. Recently, automatic and systematic search methods of reaction pathways have attracted attention. Among them, one of the most successful methods is the artificial force-induced reaction (AFIR) method. The advantage of the AFIR method is that the reaction pathways can be explored without the prejudgment of the products as well as the reaction coordinates. In this chapter, the concept and algorithms of the AFIR method are described. We also introduce the recent AFIR studies about organometallic reactions and show how the exhaustively gathered TSs contribute to a better understanding of the reaction mechanism and the origin of the selectivity.