Across both biological and social systems, rules and regulations play a crucial role in ensuring robustness and resistance to fluctuations across diverse environments. The expansion of rule systems over time is particularly relevant in contemporary political discourse, where some argue that society is over-regulated and that bureaucratic structures should be reduced. However, in the absence of a comprehensive science of regulation—one that spans all levels of living systems—we lack a rigorous framework for addressing these questions. In this talk, I propose a framework for a “science of regulation,” which integrates insights on the mechanisms and the role of randomness in regulation across biological and social systems. I address this in three parts, focusing on comparisons between biological and social structures, regulatory networks in individual systems, and the dynamics of individual regulators. First, I will introduce a unifying model that explains the evolution of abundance distributions and functional diversity in both biological and social systems, demonstrating how variations in the model’s parameters account for differences in behavior across prokaryotic cells, federal agencies, and cities. Second, I will use the legal and sport rules data to quantitatively examine the complexity of rule growth in a manner analogous to how the growth of biological regulatory networks has been examined. Third, I will explore the role of randomness with respect to individual regulators, e.g., genes that switch between transcriptionally on and off states, emphasizing potential pitfalls in interpreting probability modes in mesoscopic molecular dynamics as modes of behavior.