This volume incorporates and greatly expands upon the first edition, titled The Poetry of Alfonso X, el Sabio (London: Grant & Cutler, 1977). That work contained 384 annotated entries through to 1976. This new form takes us to 2010 and carries 1,987 entries (the new entries total 1,603, more than a 400% increase). The last entry of that early edition now carries number 638, an indication that much had been left uncovered and now has been incorporated. The fact that items are yet to be included is certain to be repeated in this new edition: some studies have not yet been discovered; others have but I have been unable to consult them personally. Others I will have overlooked or they did not come to my attention. Those I could not consult personally are marked ‘Not seen’. That is the crude nature of bibliography.

However, the amount of material since 1976 amounts to an explosion of interest not only in the Cantigas de Santa Maria (hereafter CSM), its texts, language, music and miniatures, but also – and healthfully – in Alfonso's profane poems. There are just over 1,600 new entries, a clear sign that the poems written/sponsored by the Learned King (‘El Sabio’), Alfonso X, are now attaining the prominence they richly deserve. Of the volume this one is designed to replace, John Keller wrote fifteen years ago that ‘Joseph Snow's bibliography of alfonsine poetry has served for the last few years to orient researchers, and its updating will be most welcome.’