Abstract
Science is in the midst of a Kuhnian paradigm shift, from causal, deterministic models to more probabilistic ones that emphasize systems approaches. However, systems theory is still primarily deterministic and does not readily integrate the construct of free will. In the developmental sciences, this shift has been manifesting in relational developmental systems theories (RSDTs) which highlight multi-level analyses, interindividual differences in intraindividual change, and co-action with the context. While agency is an important component in RSDTs, it is unclear how it develops. We argue that free will is a developmental construct, and that the process of the development of free will can arise in two ways: from life-changing encounters with major stressors which result in recognizing limiting influences on one's life and the development of greater self-awareness; and purposive development to increase self-regulation and mindfulness. Through purposive, mindful co-action, the individual and the network can co-evolve in positive ways.