The accuracy of reporter assays can be improved by utilizing a dual reporter system. One of the reporter genes is correlated with the promoter of interest and is used to assess the effects of specific experimental conditions, while the second reporter is used as a control and serves as a baseline response. The Dual Luciferase Reporter Gene Assay Kit allows for the sequential measurement of the activity of two different luciferases, firefly (FFL) and Renilla (RL), in a single sample. The firefly luciferase luminescence is measured first by addition of the FFL Reagent. Next, the RL Reagent is added to the same well. The RL Reagent simultaneously quenches the firefly luciferase luminescence and initiates the Renilla luciferase reaction. The light production of both reactions can be conveniently measured on a luminometer.