The updated version for the Manual of Civil Structures (MOC), a model seismic code in Mexico, was published in 2008. MOC also is incorporating guidelines for the seismic design of base-isolated structures this year 2012, being the first Mexican code to include such recommendations. This paper summarizes the most relevant aspects of these guide-lines, their relations to other guidelines worldwide and research efforts conducted in Mexico and worldwide to improve the seismic design of base-isolated structures. INTRODUCTION The Manual of Civil Structures (MOC), one of the model design codes in Mexico, was updated. This manual is fre-quently used in the entire nation in lieu of a specific code for a state or a city. The new version for this manual and all its chapters was published in 2008 [1, 2]. Among the new planned chapters, there is one devoted to the seismic design of base-isolated structures, which is going to be published in 2012 [3]. The guidelines for base isolation are based on a previous proposal that took care to make them compatible with the design philosophy of the seismic codes of Mexico and that included the seismic risk and hazard of Mexico, to ease their incorporation into model seismic codes of Mexico [4,5]. However, additional material has been reviewed, adapted and/or included, so the guidelines for base-isolated structures in MOC are a much improved version compared to the pre-vious proposal.