In this talk I will speak about the
generalization of a construction of 
Gorenstein ideal of codimension 3 to any codimension. Now we can't use
the theorem of Structure for Gorenstein ideals as in the codimension 3
case, so, the only possibility is to construct a (very good)
minimal free resolution...but the previous case gives us some hints.
If I have time, I will speak also about the "reasons" to look for
Goresntein Ideals.