In this paper I expose the structuralist view of explanation as unification, which is based on the notion of an embedding relationship between models, in its versions by Barthelborth and Forge. In addition, they maintain some different realistic theses about the explanatory power of theories. I agree with them on the model-theoretical approach but differ of their realistic theses. First, I present some criticism to those theses, and after, from a conceptualist stance, with less ontological commitment, I introduce a thesis about certain metatheoric patterns that are part of the conceptual frameworks of physical theories, which contribute to both explanatory power and unificatory force.En este artículo expongo la concepción estructuralista de...