β-arrestin serves as a core functional effector governing signal transduction of G protein-coupled receptors (GPCRs), exerting dual roles as a signal terminator and molecular scaffold. However, the molecular mechanism underlying how β-arrestin responds to diverse GPCRs and interacts with hundreds of effector proteins to mediate a broad spectrum of physiological functions remains poorly understood. A landmark original study recently published in Nature overturned the conventional view of β-arrestin as a static scaffold protein. Endogenously expressed β-arrestin undergoes liquid-liquid phase separation (LLPS) to form highly dynamic biomolecular condensates, which orchestrate compartmentalized assembly and fine-tuning of GPCR signaling complexes. This work establishes a novel paradigm centered on β-arrestin condensates for GPCR signal regulation and reshapes the molecular framework of hierarchically organized intracellular signaling networks.