I think the problem is the way files are named on the Macintosh. On the Mac, the file separator character, which is "/" on unix and "\" on dos/windows, is ":". Also, the root directory doesn't start with the separator character, but instead just starts with the volume name, which is the name of the hard disk icon on your desktop, so if your file is in the top level directory of your hard disk, and your hards disk is called for example "My Mac HD", then you would want something like > guilds <- read.table(file = "My Mac HD:untitled.teste.txt") If the file was in a sub-folder called "my folder", then you would want: > guilds <- read.table(file = "My Mac HD:my folder:untitled.teste.txt") The "current directory" is probably the directory (folder) that contains the R application, and if your data file is in the same folder, then you don't need anything except its name: > guilds <- read.table(file = "untitled.teste.txt") Also, I think from memory, that the "parent directory", which would be "../" on unix or "..\" on dos/windows, is "::" on the mac, so that > guilds <- read.table(file = "::untitled.teste.txt") would probably be the folder one level above the one containing the R application. NB All the above refers to Mac OS 7, 8, or 9. The new Mac OS X is essentially unix, and I would expect that normal unix file name conventions should apply, unless there is some backwards compatibility fix for "carbon" applications, but I'm not sure about that. There are two different versions of R available on Mac OS X, one is pure unix running under the X11 window system, and the other is a carbon application using the native Macintosh windowing system, so they might behave differently. I hope this helps, Luke Whitaker