Abstract. The millisecond time resolution achieved by Energy Dispersive EXAFS (EDE) and the high stability provided by the unmoved optical components make this technique very attractive to study chemical reactions and elucidate reactive intermediate species. Great progress has been made on the EDE study of the problematic in situ experiments of reactions in solution. Herein, limitations and solutions for the study of these systems are given. Two examples of catalytic reactions followed in situ and carried out in a stopped-flow/UV-Vis spectroscopy/EDE set-up are shown.