In addition to Mt St Helens climbing permits, it's also get close to the start of the Enchantments lottery period. Unlike St Helens permits, there is no first-come, first-served. Instead the application window runs from February 22 - March 13, and after that the lottery is held.

June 15 to October 15, 2012 reserved permits are required for overnight trips. Since demand for overnight permits exceeds supply a lottery is held annually. For the 2012 season the lottery application period will run from February 22, 2012 until 11:59 PM on March 13, 2012. All applications received during this period will be randomly drawn after March 13. The application fee is $6.00. 

For more information, see the Enchantments permit page on recreation.gov.