As of October 2011, all of the programs in the collection are free to download. Go to the Contents page and select the program you wish to download. There will be a link on the page where you may download an archive file with the description and source code for the program in question. This file will be in the ZIP format without encryption or passwords. In most cases, there will also be instructions and sample cases. This program page will usually have a link to a page of references for the program. Some of the reference documents may be downloaded directly from the PDAS website. See below if you want a complete file of all the programs.