The role of the psycho-oncologist in the psychosocial care of the families of patients with cancer in advanced stages and palliative care is one of the most important areas of intervention in family-centered psycho-oncology, because the progression of cancer and the patient's entry into the palliative care stage can profoundly affect the emotional, social, and functional structure of the family. In this stage, in addition to facing physical symptoms and reducing the patient's abilities, the family may face fear of death, premature grief, feelings of helplessness, anxiety about the future, caregiver pressure, financial problems, and changes in family roles. Palliative care is performed with the aim of maintaining the quality of life, reducing suffering, and supporting the patient and family during the illness, and therefore the psychosocial health of the family is an integral part of comprehensive care. The theoretical foundations of psycho-oncological interventions in this stage are based on the psychosocial and spiritual biomodel, the theory of family systems, the theory of stress and coping, and the family-centered care approach, and considers the family as an interconnected system in which the change in the status of each member can affect the other members. In this situation, the psycho-oncologist first assesses the psychological and social status of the family and takes into account factors such as anxiety, depression, distress, guilt, helplessness, caregiver burnout, quality of relationships, social support, economic problems, and concerns about the future. One of his most important tasks is to identify the difference between the family's natural response to difficult illness situations and severe and disruptive distress, because sadness, fear, and worry are expected reactions in the face of advanced cancer, but when these emotions seriously disrupt a person's functioning, the need for specialized intervention increases. In the cognitive-behavioral approach, the psycho-oncologist helps family members identify catastrophic thoughts and unrealistic beliefs about illness, death, and caring responsibility, and distinguishes between medical reality and their own subjective interpretations. For example, the caregiver may think that he or she should eliminate all of the patient's pain and suffering, and if he is unable to do so, he or she will hold himself responsible, while the goal of palliative care is not to completely eliminate all the difficulties of the disease, but to reduce suffering and maintain the highest possible quality of life. The psycho-oncologist can work with the treatment team to help the family better understand the concept of palliative care and not simply equate it as ending treatment or abandoning the patient. It is the responsibility of the treatment team to provide specialized medical information, but the psycho-oncologist can process and manage the family's emotional reactions to this information. One of the important applications of the intervention is to support the family in adjusting to the patient's changing role, as the decrease in the patient's independence may cause the spouse or children to gradually take on more responsibilities. This change of role can create feelings of fatigue, pressure, and even family conflict, which is why planning for the division of responsibilities is so important. By identifying the resources available in the family and society, the psycho-oncologist can help to distribute caregiver duties more evenly and prevent all responsibilities from focusing on one caregiver. Communication skills training is also an essential pillar of psychosocial care, as the family may avoid talking about death, the patient's fears, and desires, and this silence can increase loneliness and anxiety. Creating a safe space for dialogue allows the patient and family members to express their concerns and talk about their emotional and practical needs. In this process, respect for the patient's independence, preferences, and values is of fundamental importance, and the psycho-oncologist should not replace the patient or the medical team in treatment decisions. If the patient wishes, family sessions can be used to facilitate conversations about care goals, the role of family members, and future concerns. Another important area is pre-existing grief management; family members may experience feelings of loss, sadness, anger, and nostalgia before the patient's death. By providing space to process these emotions, a psycho-oncologist can help the family recognize the experience and face the reality of the illness without suppressing or denying the emotions. Spiritual support also becomes important in some families, as the advanced illness may raise questions about the meaning of life, hope, suffering, death, and personal values. Meaning-based interventions can help family members identify their important sources of meaning and values without imposing specific beliefs. Paying attention to the children and adolescents in the family is also essential, as they may perceive a decrease in the patient's ability or changes in the home environment but may not be able to express their feelings properly. Training parents to have age-appropriate dialogue and to respond honestly and supportively can help create a sense of security. Another job of a psycho-oncologist is to support primary caregivers, as long-term care can be associated with fatigue, sleep disturbances, limited social activities, and burnout. Self-care training, stress management skills, using a support network, and accepting the help of others can increase the caregiver's capacity. Paying attention to the caregiver does not mean diminishing the importance of the patient, but rather being part of the sustainable care of the whole family. Relaxation, breathing, mindfulness, and emotion regulation techniques can also be used to manage anxiety and tension in difficult situations. In some families, noticing severe pain or symptoms makes the patient feel helpless, and the caregiver thinks they need to solve the problem personally; the psycho-oncologist can help them differentiate between their psychological supportive role and the medical responsibilities of the treatment team. Working closely with a doctor, nurse, palliative care specialist, social worker, and other multidisciplinary team members is a requirement of this approach, as many family problems are not purely psychological in nature and are also related to physical, economic, social, or organizational issues. Referral of the family to social services, social support, or home care resources, if any, can reduce the practical pressure of care. An important challenge at this stage is the conflict between hope and acceptance of the reality of the disease; some family members may avoid talking about the prognosis or death, and others may come to terms with reality sooner than the patient. The psycho-oncologist should avoid imposing a particular style of exposure and respect the pace of adjustment of each individual. Cultural and religious differences, family beliefs about death, attitudes toward palliative care, and health literacy levels can also influence the acceptance of interventions. Another challenge is economic pressure and limited access to specialized services, which can reduce the family's ability to receive ongoing support. One of the limitations of psycho-oncological interventions is that it is not possible to eliminate the reality of suffering caused by advanced cancer, loss and death, and the psychological goal should not be to create unrealistic optimism. Also, the severity of the patient's physical symptoms, economic conditions, quality of palliative care services, and the level of social support are factors that are outside the direct control of the psycho-oncologist. Therefore, the intervention should be realistic, individual-centered, and tailored to the needs of each family. It is recommended that the family's psychosocial screening of the advanced stages of the disease be carried out on a regular basis, and psychological support should be continued during palliative care and after the patient's death, if needed. Educating the family about emotional reactions, strengthening communication skills, supporting caregivers, facilitating family conversations, paying attention to semantic needs, and building effective communication with the palliative care team can provide a comprehensive framework for these interventions. Ultimately, the psycho-oncologist in caring for the families of patients with advanced cancer does not only reduce anxiety and depression, but also works to strengthen the family's capacity to tolerate uncertainty, maintain communication, manage new roles, support the patient, take care of oneself, and cope with grief and loss more healthily. Such an approach transforms palliative care from a purely symptom control program to a family-centered process in which the patient's and family's psychological and social suffering are simultaneously addressed, and dignity, communication, and quality of life are maintained as much as possible at all stages of the disease.