Since May 2010, the lavaan package is available on CRAN. Therefore, to install lavaan, simply start up R, and type:
You can check if the installation was succesful by typing
When the package is loaded, a startup message will be displayed showing the version number, and a reminder that this is beta software:
This is lavaan 0.6-1 lavaan is BETA software! Please report any bugs.
If you see this message, you are ready to start.