hi All: My computer is a Mac G5. And I downloaded FSL for Mac G5, 3.3.11. I unzipped the FSL package, and tried to setup the environment variable. I followed every step on FSL website. I copied the online script into both .bash_profile and .bashrc file, and following are my exact script: export FSLDIR=/Users/xuelin/fsl . ${FSLDIR}/etc/fslconf/fsl.sh PATH=${FSLDIR}/bin:${PATH} export FSLDIR PATH export DISPLAY=localhost:0.0 where /Users/xuelin/fsl is the location where I installed my FSL, and I am sure it is correct. When I echo $FSLDIR, the console reflects the correct value, which is: /Users/xuelin/fsl. But when I type "fsl" in console, it shows: bash: fsl: command not found . I dont know how I should modified the .bash_profile/.bashrc file to make FSL work. Or this is due to other reasons? Does anyone have same problemm before? Thanks a lot Xuelin