Looking to try to identify the name of a series (or its individual books) which I read in the 90's. I've only read the first one/two in the series and I believe that they were still being written at the time I was reading them, though I may be mistaken in this.
The basic premise for the series involved the ending of the "Age of Reason" (I believe they referred to it as such in the books themselves), which allowed the gradual return of magical creatures into the world. Definite presence of at least one Dragon in the books, and the Tuath(a) Dé Danann.
I know there was one or more people on a quest, though I cannot remember what the were specifically searching for.
I have the impression of the context of a world unprepared for the return of magic, and a small group of people attempting to prevent it, or at least mitigate the damage it will cause, working with/for the Tuath(a) Dé Danann, though I believe it was somewhat reluctantly, and with the understanding that they had their own goals which were not necessarily friendly.