Systems modeling provides an integrated framework to capture and analyze diverse and multidisciplinary data in a standardized manner. The authors present the Integrative Oncology Systems Model (IOSM) to help assess the impact of behavior modification and various therapeutic interventions on cancer development and progression and the resultant effect on survival and quality of life outcomes. Keywords cancer, prevention, recurrence, progression, systems modeling, systems dynamics, integrative oncology, integrative medicine, complementary medicineIntegrative oncology is the approach to oncology that combines conventional interventions (ie, surgery, radiation, chemotherapy, etc), nonconventional modalities (ie, acupuncture, massage, meditation, etc), and behavioral/lifestyle education to help patients improve their quality of life (psychological, spiritual, and physical) and disease-specific outcomes and prevent disease. Integrative oncology is personalized medicine that takes into account each individual's unique circumstances and disease process to customize treatment programs. The concept of integrative oncology creates the significant challenge of trying to understand the complex relationships and effects of numerous dynamic, interdependent parameters (eg, psychosocial and biological factors, comorbidities, treatments, etc) that occur before, during, and after a diagnosis of cancer.The Society for Integrative Oncology's recently formed Integrative Oncology Systems Modeling Working Group is developing the Integrative Oncology System Model (IOSM), an integrated framework to capture and analyze diverse and multidisciplinary data in a standardized manner. The IOSM is based on both analysis and empirical data and will eventually be used to simulate how various interventions and behavioral changes might dynamically modulate cancer-specific and other health-related outcomes. The IOSM is in the earliest stages of development and, currently, is only a visual/graphical representation of the complexity of a whole systems approach to integrative cancer care. At this time, the present version of the IOSM can be used as an educational tool to demonstrate potential interactions among numerous parameters that may affect outcomes. As the IOSM becomes more sophisticated and robust, we expect that it will become a helpful tool for tailoring individualized integrative oncology recommendations for our patients.