DESCRIPTION: (Applicant's Description) Core D will provide computer software support for the four research projects and three other cores. All of the projects require augmentation of the existing treatment planning, optimization, and delivery systems (UMPlan, UMOpt, and CCRS/VARiS) to incorporate more advanced techniques as they are developed as part of this grant. This core will improve and enhance the software applications used for the studies proposed in the research projects, which will facilitate further study of these techniques in a routine clinical setting. The tasks of the treatment delivery and quality assurance cores will also be assisted by the development and implementation of requested software tools into the software systems used for that work. Project 1 requires implementation of new optimization strategies into the optimization framework, UMOpt. Projects 2 and 3 require enhancement of clinical computer software such as the CCRS and VARiS systems in order to help measure the efficacy of methods explored within those projects, and Project 2 will also involve additional dose calculation algorithm and dose distribution analysis software. One Project requires enhanced planning and optimization tools that assist in the study of the effects of tumor dose escalation and normal tissue sparing. The dosimetry and treatment delivery core will be supported with software tools necessary for analysis of gathered data, and with integration tools needed to exchange data between research projects and clinical software systems. This core will provide, to the projects and cores, a stable, well-maintained computing environment. This includes such basic elements as a programming staff well versed in software design and test methodology, a comprehensive and reliable computer network, archives of research data, and the personnel and tools necessary for management and acquisition of computer resources.