“…So, the example analyzed in this paper (semiclassical Jacobi-type OP with respect to a moment functional of class s = 4) is, probably, a good starting point, since other semiclassical cases like Laguerre-type, Hermite-type (see Álvarez-Nodarse and Marcellán, 1995;Koekoek and Koekoek, 1991;Koekoek, 1988), and, of course, the very classical OP should be connected by limit transitions to the semiclassical Jacobi-type OP as the starting family. The present paper helps us to understand the analysis of semiclassical OP (very close to the classical ones), and then one has a good basis for studying other extensions, for which there are quite a few possibilities for research.…”