A cancer diagnosis poses a stressful situation not only for the patient but also for family members. In particular, spouses experience mental and social strains comparable to that of patients. Spouses are the most important sources of emotional and practical support for the patients. The cancer disease can lead to profound changes in the relationship functioning with e. g. role changes or restrictions of couples’ activities as well as sexual functioning, which makes adaptation processes necessary. Topics regarding sexuality often lead to speechlessness between patient and partner and also between the couple and clinicians. An open communication of sexual topics, ideally initiated by the medical team, would be advisable. For couples an open communication as well as enhancement of dyadic coping (common coping efforts of the couple) appears to be helpful in reducing distress and enhancing the quality of life. Couple-based interventions are a useful support for couples during the adaptation and coping process.