My thanks to all who have contributed to this thread (Thanh, Reinhard, Martin, Hartmut, et al). To clarify, Reinhard is quite right : my LaTeX expertise is so non-existent that I didn't consider for one second doing what would have been 2nd-nature had I been working in Plain : hack the o/p routine. But my reason for sending the message to the PdfTeX developers was that PdfTeX is its own driver, and as drivers frequently provide n-up capability, it seemed by no means impossible that PdfTeX might do the same. As it does not, and as the hyperlinks are essential (the TOC refers to the start of each chapter), I will need a solution that preserves these. I have not yet had time to investigate Pdfpages or Quire, but both look interesting and I will report back once I know whether either or both preserver hyperlinks. As PdfTeX does /not/ provide n-up capability inately, would it be possible to request this for consideration as a future enhancement ? ** Phil.