As I indicated in the overview of polyadenylation, this process is mediated by a complex of proteins called, naturally enough, the polyadenylation apparatus. This machinery has been reviewed many times over the years, and the review I pointed to earlier provides a nice overview of the subunits involved. An illustration from this review is below the fold at the end of the essay; this illustration and the review will serve as the source for much of this information, and will take the place of what would be a long list of citations that pertain to the details that follow. Rather than re-invent the wheel, what I thought I would do is to summarize things taking a different approach. Thus, what I will try to do in the next few essays is to discuss things from the perspective of the biochemical activities one finds associated with the complex, with special attention being paid to unexpected or unexplained aspects of the complex. As well as being a list, I hope that these essays will raise in readers’ minds one or two questions about the process, questions likely without answers at the moment.