There are many fields in Astrophysics with a strong need of direct and rigorous comparisons between theoretical models or simulations and real data. However, the different architectures, programming codes, formats, etc, make it, most of the times, extremely difficult and inefficient.
One of the aims of the Virtual Observatory initiative is the full interoperability between theoretical and observed data. In the Spanish VO we work also in this subject, helping to define new protocols for theoretical data, implementing these protocols for several models and developing services and applications that use those resources.
