This is a word of warning to those package authors who want to make use of Tcl/Tk extensions. First, please document them in the DESCRIPTION file, in the SystemRequirements field. Second, people have been recommending ActiveTcl. The latest ActiveTcl releases are much smaller, and it seems this is because the extensions are not included so those recommendations will need to be changed. I am contemplating adding a few extensions to the R 2.7.0 Windows distribution -- certainly BWidget and Tktable seem fairly easy to do. The only other Tcl/Tk extensions I have found are Iwidgets, which might not be so easy (it requires itcl and itk) and Img (not easy). (There are some mentioned in packages which I have not found.) There are a number of additional widgets in Tk 8.5 that might be easier to make use of (R 2.7.0 for Windows will ship with Tcl/Tk 8.5.x). Ideally someone who wants to make use of these extensions will volunteer to distribute Windows versions of them -- I expect Duncan Murdoch would be happy to include them in Rtools.exe if the licence conditions allow. -- Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595