The European population is ageing rapidly and with age an increase in co-morbidites and a decline in abilities is seen. Frailty is an often-used term to indicate a higher risk to adverse health outcomes. This seems to be a simple concept however in daily practice it is awkward for physiotherapists to work with the term frailty. Frailty is complex and dynamic and is often not recognized by the patient themselves. In this lecture the multiple dimensions of frailty will be addressed and the usefulness in daily practice for physical therapists.