There is a high prevalence of frailty amongst older patients in hospital settings. Frailty guidelines exist but implementation to date has been challenging. Understanding health professional attitudes, knowledge, and beliefs about frailty is critical in understanding barriers and enablers to guideline implementation, and the aim of this study was to understand these in rehabilitation multidisciplinary teams in hospital settings. Twenty-three semistructured interviews were conducted with health professionals working in multidisciplinary teams on geriatric and rehabilitation wards in Adelaide and Sydney, Australia. Interviews were audio recorded, transcribed, and coded by 2 researchers. A codebook was created and interviews were recoded and applied to the Framework Method of thematic analysis. Three domains were developed: diagnosing frailty, communicating about frailty, and managing frailty. Within these domains, 8 themes were identified: (1) diagnosing frailty has questionable benefits, (2) clinicians don't use frailty screening tools, (3) frailty can be diagnosed on appearance and history, (4) frailty has a stigma, (5) clinicians don't use the word "frail" with patients, (6) frailty isn't always reversible, (7) there is a lack of continuity of care after acute admission, and (8) the community setting lacks resources. Implementation of frailty guidelines will remain challenging while staff avoid using the term "frail," don't perceive benefit of using screening tools, and focus on the individual aspects of frailty rather than the syndrome holistically. Clinical champions and education about frailty identification, reversibility, management, and communication techniques may improve the implementation of frailty guidelines in hospitals.