The Neurovisceral Integration Model (NIM) is one of the most influential psychophysiological models addressing the interplay between the autonomic (ANS) and central nervous system (CNS). In their groundbreaking conceptual work, integrating autonomic, attentional, and affective systems into a functional and structural network, Thayer & Lane laid the foundation for empirical research in the past two decades. The present paper provides a principal outline aiming to reflect and further elaborate on the model from a dynamic developmental perspective. The central question at hand is, how does neurovisceral integration develop (early in life)? By reviewing the existing evidence, it is illustrated that key components of the model, both, on a physiological and psychological level, undergo extensive change early in the course of life. This sensitive period of human development seems key for our understanding of the integrated action of the ANS and CNS in emotion across the lifespan. Early life events may interfere with the fine-tuned interplay of this shared neural circuitry resulting in long-term dysfunction and psychiatric illness. In the absence of longitudinal data covering the entire co-development of the ANS and CNS from early childhood to adolescence into early adulthood, it is suggested, that vagal activity and its normative increase in adolescence is a key premise for normative brain development on a structural and functional level, subsequent psychological functioning and adaptive regulation. Implications from this dynamic perspective and suggestions for future research in the field of developmental psychophysiology are discussed.