In October 2007, we began a staged Beta Release of the Common Astronomy Software Applications (CASA) data reduction package. This software is under development in support of the ALMA and EVLA projects, but is intended to also be of general use for radio astronomy data post-processing. This staged release allowed personnel involved in the construction, operations, and advisory committees for ALMA and EVLA to adopt early use of the package for commissioning, development of user support capabilities, and to provide feedback to the CASA team.

Through mid 2008, access to the Beta and support for CASA users was restricted to ALMA and EVLA project personnel and key scientific advisory committee members, due to limited user support personnel. During this period the CASA team has concentrated on completing the suite of basic functionality and pursuing advanced algorithm development needed for ALMA and EVLA. In mid 2008, we are expanding the availability of the Beta Release to others in the community as our user support capabilities ramp up.

CASA remained in Beta Release until least December 2009. During the beta release period, we provided "patches" to the release at least twice a year in order to fold in ongoing developments. Patches were also made as needed to fix any egregious bugs. The first such "Beta Patch 1.0" was made available in early April. The second patch ("Beta Patch 2.0") was made released on July 7, 2008 (and was used for CASA tutorials at the June 2008 NRAO Synthesis Summer school), with the third on December 1, 2008 ("Beta Patch 3.0") and updated ("Beta Patch 3.1") on January 21, 2009. The final beta release was ("Beta Patch 4" version 2.4.0) issued on June 24, 2009.