Design-Based Research (DBR) has been a tool of the learning sciences since the early 1990s, used as a way to improve and study learning environments. Using an iterative process of design with the goal of reining theories of learning, researchers and educators now use DBR seek to identify "how" to make a learning environment work. They then draw theories from the research findings that can be shared with a larger community. In this way, knowledge of design principles accumulates within a community for the improvement of learning outcomes. With few exceptions, including some after-school clubs, DBR has been used primarily in formal education. Yet, I argue for the implementation of a DBR-style approach in the design and research of informal learning environments as a way for educators and researchers to expand current evaluation offerings. The end goal of the adoption of a DBR approach would be that museum educators can learn from one another, improve those learning environments, and avoid duplicating research and evaluation work. In this article, I provide an overview of DBR along with an example of how it can be implemented in the study of a science center exhibit. (Contains 12 notes.)