Our goal is to establish a science of the individual, grounded in analysis of individual patterns of growth.We start with a focus on how individuals grow, based on models of pathways and contexts that shape development.Our argument is that individuals grow in distinctive ways, showing patterns of variability that are not captured by models of average or mean growth.The average does not represent normal growth.Instead individuals show distinctive growth patterns, often unique.Different people grow along distinct pathways, which typically show extensive variability.Both pathways for learning and patterns of cellular growth in cancer document this variability.To find consistent patterns of growth, scientists need to focus on consistent individual pathways and differences, not averages or means.Concepts from dynamic systems can be used to model individual pathways and patterns.