Due to the unique microstructures formed during welding and additive manufacturing processes, crack-type defects—such as hot cracking, particularly solidification cracking—frequently occur. The prevention of such cracking is a critical issue for practical applications, as it reduces the likelihood of material failure and ensures the long service life of components. Solidification cracking occurs in the temperature range between the liquidus and solidus, resulting from strains induced by solidification shrinkage in combination with constraint forces acting on the remaining liquid phase. Therefore, a thorough understanding of the relationship between the solidification sequence and crack formation, as well as the factors influencing susceptibility to solidification cracking, is essential. This paper presents recent insights into the factors that are known to influence solidification cracking in austenitic stainless steels such as the amount of ferrite and the formation of secondary phases. Further, the hot ductility curve is discussed as an evaluation method for solidification cracking susceptibility. This knowledge contributes to mitigating solidification cracking in fusion welding and related additive manufacturing of stainless steels.