Cognitive Remediation and Emotion Skills Training (CREST) is a method successfully implemented in the treatment of eating disorders, that helps improve cognitive and emotional deficits. As patients with eating disorders and substance abuse have similar neuropsychological impairments and have also a high co-morbidity in both disorders, we can consider using CREST in the treatment of addiction. The introduction part is based on views of various authors on the issue of eating disorders, their comorbid psychiatric diseases and mechanisms associated with eating disorders and substance addiction. Further I describe the neuropsychological deficits found in both diseases, the possibilities of their rehabilitation and finally I present the CREST program. The aim of the research was to evaluate the quality of the program implementation. I focused on comparing the process, satisfaction and benefit of the intervention in 4 patients with eating disorders and 8 patients with substance addiction co-morbidity. Data were collected from the diagnostic screening of substance-related disorders, by analyzing medical documentation and participating observations in 10 CREST lessons. Key data source were also satisfaction and benefit questionnaires, and the focus group after the end of the program. The results showed,...