Background: Old age–based discrimination is observed as the most tolerated prejudice in society and has also been witnessed in healthcare institutions. Aims: The aim of this study is to explore age-based discrimination in healthcare institutions as perceived by seniors and students of Medicine and Nursing. Research design: A multi-method study design, by involving a triangulation design. Participants and research context: A purposeful sample of individuals aged 65+ (n = 80) and medical and nursing students (n = 100) in the eastern (...) region of Poland. Ethical considerations: Ethical approval of the research protocol was received from the Ethics Committee at the Medical University of Lublin. Findings: ‘Old age’ was perceived by groups of participants based on three themes: (a) positive, (b) negative and (c) neutral connotations. The negative connotations predominated. The beginning of old age was defined by the metric of age and described by showing the complexity of the ageing process involving subjective, objective and societal aspects. Experience of age discrimination in healthcare institutions was reported by 24 (30%) seniors and witnessed by 47 (47%) students surveyed and for both groups occurred mainly at the hospital level and by physicians. Only 48 students (48%) declared a willingness to work with the older people in the future, and barriers were reported at the personal and professional levels, and also in some visions of older people. Conclusion: The conceptualization of old age as reported by seniors and students mainly carried negative connotations, reflecting the profoundly based stereotypes within society regarding the older people. Seniors have reported being exposed to ageism and have witnessed ageism episodes in HCIs; also, students have faced ageism episodes during their clinical education. There is a need for ethical education within medical and nursing courses to shape positive attitudes towards the older people. A positive vision of ageing should be promoted not only among young people but also among adults and older people to avoid self-stereotyping of older people and seeing old age from negative perspective. (shrink)