Abstract. This case study examines the effectiveness of an Addiction Severity Index (EuropASI) as a standardized instrument for elaboration of an individual needs assessment for a person with drug misuse. The study is based on a single case study design done in the Centre for people with mental and behavioral disorders due to the misuse of psychoactive substances "Pink House" in Sofia. The person underwent a needs assessment through a semi-structured interview with the Addiction Severity Index.  Scores on the individual ASI categories and the interviewer's assessment of the severity of dependence were used to measure the person's problems in seven domains (health, family and social relationships, employment, alcohol and drug use, mental health, and legal issues). Conducting a needs assessment by Addiction Severity Index (EuropASI) provides reliable information about various aspects of the person's life that have contributed to the development and maintenance of drug dependence. This assessment is a good basis for drawing up a profile of the person and for planning the next steps for social work with people with drug dependence syndrome. The application of a semi-structured interview with the EuropASI questionnaire represents a reliable and valid tool that can be applied to carry out a needs assessment in social work with substance dependent individuals.
Keywords: needs assessment, degree of dependency, Addiction Severity Index (EuropASI), psychoactive substances, social work, semi-structured interview