This study was conducted to assess the content validity of the Modified Engulfment Scale - Family Version (MES-FV) which measures the impact of schizophrenia on a family member’s self-concept and on the identity of the family as a whole. The concept of family engulfment offers a perspective for understanding how a family member’s self-concept and a family’s identity might incorporate the experience of mental illness. Evidence of content validity was sought by computing a content validity index (CVI), based on ratings of item relevance by seven experts. Case studies, and domain and item matching were also used to obtain evidence pertaining to the content validity of the scale. The study results show strong evidence for the content validity of the MES-FV. The results of the case studies, and domain and item matching were particularly useful in extending the understanding of the relevance ratings (CVIs) which were given for certain MES-FV items.