Psychobiological systems theory is a relational approach to development that challenges the longstanding views that (1) genetic and environmental influences on the phenotype can be meaningfully partitioned and that (2) genes are capable of directly specifying phenotypes. Gilbert Gottlieb's theoretical innovations including the notion of "probabilistic epigenesis" (which holds that development is a probabilistic and contingent phenomenon regulated jointly by organismic and contextual factors), the concept of the "development manifold" (which holds that changes in the sensory aspects of species-typical developmental conditions will alter usual developmental outcomes), his emphasis on the role of "non-obvious experience" in species-typical development, and his proposal that "developmentally-based changes in behavior" can lead to the evolution of novel phenotypes prior to genetic change have all been recognized as key contributions to developmental and evolutionary theory by philosophers, biologists, psychobiologists, and developmental psychologists. Vanessa Lux's article, "With Gottlieb beyond Gottlieb" (Lux, 2013), extends Gottlieb's ground-breaking work by outlining a new model of how to integrate contemporary molecular epigenetics into the developmental psychobiological framework. Lux's expanded version of Gottlieb's model of psychobiological development provides a basis to begin to unpack the complex links between genetic and neural activity. Developmental scientists clearly have their work cut out for them and Lux's expanded model of Gottlieb's original efforts in psychobiological systems theory shows considerable promise for addressing this complexity in the post-genomic era.