This is a keynote presentation given at AERA on developing a validity agenda for growth models in a large scale (e.g., state) setting. The emphasis of this presentation was to indicate that growth models and the validity agenda designed to provide evidence in supporting the claims to be made need to be personalized to meet the local or state-specific goals, purposes and context. The takeaways from the presentation were (a) large scale assessments, national databases, validity work and technology are components that cannot be separated and must exist to implement growth models well; (b) there are a number of components that must be in place when introducing growth models in large scale settings (e.g., states); (c) it is our professional responsibility to make sure that there is evidence to support the claims being made; (d) a short- and long-term validity agenda are needed to permit the collection of evidence across all component of the growth model that represent fundamentally stating the claims to be made and evaluating whether the claims can be supported; (e) because there exist a variety of goals and diverse contexts, there is no one growth model and the design of the validity agenda will be personalized and end up being similarly varied; (f) start with the score report as the concrete expression of the claims being made and make sure that each component is validated; and (g) there a lot of work that needs to be done and it's hard work, so the targets of these results (children, teachers, and administrators) need your thinking and efforts.