I found the bioconductor message annoying enough to track down and remove. The message is displayed from within the .onAttach function within the Biobase package. File: $RHOME/library/Biobase/R/all.rda (On my intel MAC) Commenting out the message lines stops the startup message. 1) Backup original all.rda 2) Clear all packages from the search path except "package:base" and ".GlobalEnv" 3) load all.rda 4) paste in altered .onAttach function 5) save(list=ls(all.names=T), 'all.rda') I'm sure there are better ways of changing one function within a data file, but this one worked for me. Hope this helps! Alastair.