There is little doubt that schizophrenia (SZ) and obsessive-compulsive disorder (OCD) are among the most severe disorders to impact humanity. They are both common, significantly disabling and have the tendency to strike during critical developmental periods in a young person's life. Schizophrenia affects approximately 1% of the global population and OCD has a lifetime prevalence of between 2% and 3% in the general population. The comorbidities in both SZ and OCD are common and frequently diagnosed, and research has generally found that comorbidities are associated with conditions that are more complex to diagnose and treat, and often result in less favorable prognoses. We review the research that has taken place regarding the co-occurrence of SZ and OCD, discuss it's theoretical conceptulization and clinical differentiation and diagnosis. We then propose recommendations for the best practice of cognitive behavioral therapy in this difficult population, as well as areas that need exploration for future research.