The impact of informal care to both the patients' and carers' physical and psychological well-being is studied in detail. However, despite the social and clinical impact of this role, decision pathways and individual motives in becoming a caregiver have attracted less attention. The study aims to explore individual and collective decision pathways of becoming an informal caregiver, as well as individual motives and contextual factors that contribute to this role during cancer treatment in Turkey. Fourty-nine women and 10 men informal caregivers were recruited from the oncology department of the Marmara Medical School Hospital in Istanbul. Two trained research assistants carried out semi-structured interviews. A qualitative content analysis was conducted. Results indicated that individual decisions, social and family network decisions, role-dependent obligations were the primary paths of decision of becoming an informal caregiver. Three personal motives for caregiving were sense of social responsibility and obligation, personal and emotional connectedness, and sense of competence. The decision to become caregivers are closely connected with individual experiences and social and cultural factors. Understanding the individual and cultural context of findings might contribute to the design of appropriate support programs for informal caregivers in oncology clinics.