OWASP's projects cover many aspects of application security. We build documents, tools, teaching environments, guidelines, checklists, and other materials to help organizations improve their capability to produce secure code. For details on all the OWASP projects, please see the OWASP Project page.
Open Web Application Security Project
The Open Web Application Security Project (OWASP) is an open community dedicated to enabling organizations to develop, purchase, and maintain applications that can be trusted. All of the OWASP tools, documents, forums, and chapters are free and open to anyone interested in improving application security. We advocate approaching application security as a people, process, and technology problem because the most effective approaches to application security include improvements in all of these areas. We can be found at http://www.owasp.org