The goal of this seminar is to bring together experts in regulation of gene expression—spanning multiple model systems and scientific disciplines—to develop theoretical and computational frameworks that can predict the input-output relationship for gene regulatory circuits and the effects of genetic perturbations on their function. Regulation of gene expression is a fundamental biological process, required for organisms to maintain homeostasis, respond to environmental signals, and differentiate into multiple cell types. Changes in gene expression are implicated in human disease and other types of phenotypic variation in natural populations; on longer evolutionary timescales, they underlie acquisition of new organismal morphologies. Yet, except in the most well studied microbial systems, we cannot predict gene expression outputs from known chemical inputs, or how perturbations to the molecular components will affect the input-output relationship. Seminar organizers believe the time is right to bring together experimental and theoretical scientists from applied mathematics, engineering, physics, and biology to explore the challenge of developing predictive mathematical frameworks for regulation of gene expression. The seminar will examine the opportunities and challenges that we face in making gene regulation into a quantitative, predictive science. Participants will dig deeply into challenges and controversies facing the field, and establish an active scientific community around this emerging research area.