Attachment security has been identified as an important buffer of distress in patients with cancer and other medical illnesses but current measures have not been adapted for this population who may be older, in long-term stable relationships, and suffering from considerable disease burden. This study reports on (1) the psychometric properties of a modified 36-item Experiences in Close Relationships scale (ECR), adapted for this population; and (2) the validity of a brief 16-item version of our modified scale.