Enhancing substitution of substances of concern with less hazardous alternatives will remain a key challenge for chemicals management in the coming years and is a central aim of ⁠REACH⁠. This study analyses the support of substitution, which is the use of less hazardous alternatives for substances of concern, by instruments of the REACH regulation as for example during restriction and authorisation procedures and elaborated concrete recommendations for improvements. The analysis addresses two key questions: How does REACH actually support substitution of substances of concern? How could changes in REACH or its implementation enhance the support of substitution by REACH?