This report to the congress “Materials issues in Art and Archaeology IV Cancun 1994”, deals with the materials that intervene in the construction of our traditionalbuildings, basically of those of the viceregal epoch. It is to clarify the term viceregalbecause most of you are familiarized with the noun “colonial” that is usually applied, inappropriately, to that epoch and to its architecture, word derived of the used term, now used accurately, in the architecture and in the culture of the north neighbour countries, due to the circumstances of their historic-political development. The culture of Mexico is of crossbreeding. What Mexico is today was never a“ colony ”of anybody, it was called Viceroyalty of New Spain until it became an independent nation. And although you have noticed I am not an expert in the English Language, so I apologize, it seems to me that the equivalent terms are Viceregal Period and Viceregal Architecture. We can now start with the introduction.