With today's high demand for online applications and services running on the Internet, software has become a vital component in our lives. With every revolutionary technology comes challenges unique to its characteristics; for online applications, security is one huge concern and challenge. Currently, there are several schemes that address application security at various phases of the application development cycle including the requirement gathering, revision, and testing phases. These solutions can be expensive requiring high overhead, time and expertise to implement. We introduce a Programming Methodology based on the N-Version Application Security Automation (NVASA) Framework. The NVASA Framework reduces the security overhead during the software development life cycle (SDLC) while increasing the overall security of the application. Moreover, the NVASA Framework adds a scheme of protection against zero-day application exploits. In the praxis we investigate schemes to reduce the overhead associated with the implementation of the N-Version Programming Methodology. Furthermore, we develop the NVASA Framework for cloud computing to provide cost-effective security for cloud applications. Experimental results demonstrate that the NVASA framework enhances security compared to current security methods in standalone applications. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]