Psychological adjustment of siblings of children with cancer is not well understood. Faced with paediatric cancer, al1 family members are affected by changes in routines and relationships due to the demands of the illness and treatment regimens. Quantitative and qualitative research methods were used to examine the following: psychological adjustment OP siblings; congruency between parent and sibling reports of sibling adjustment; the role of siblings' perceptions of communication, relationships, global self-worth in their psychological adjustment; and evaluation of the Siblings Coping Together program (Barrera, Greenberg, & Booth, 1996). Forty siblings and one parent per Family participated in this study. Twenty-five siblings and parents completed pre- and post-assessment measures for program evaluation. Ten siblings and eleven parents completed a semi-structured interview.