The present invention relates to methods for measuring compound efficacy and potency on nuclear receptor-co-regulator interaction, comprising the steps of (a) co-incubating at least one nuclear receptor and at least one compound under conditions that allow interaction; (b) co-incubating the nuclear receptor-compound mixture of step (a) with an array of co-regulators, under conditions that allow compound modulated receptor-co-regulator interaction; (c) determination of compound-modulated receptor-co-regulator interaction in function B of co-regulator concentration, and (d) determination of compound-modulated receptor-co-regulator interaction in function of compound concentration; wherein steps (c) and (d) are performed in a single assay.