Extract: The acknowledgement of protein-energy malnutrition (PEM) as one of “…the most serious nutritional problems of our time” was actually made by Dr Butterworth Jr in 1974 in his seminal article, “the skeleton in the hospital closet” (1). In most cases, major health problems prevalent in the 1970s have been addressed and improved, such as vast improvements in vaccination rates, pain management and contraception efficacy (2-4). But when it comes to PEM, the continuing high prevalence across all settings (10 – 65% in our home-dwelling, hospitalised and institutionalised elderly) (5-8) and hefty economic burden (>USD$156 billion per annum) (9-11) at first appears to suggest that medicine and medical nutrition therapy may have failed to achieve any significant improvement in the past 40 years. However, PEM (the unintentional loss of lean tissues caused by inadequate energy, protein and nutrient intake) is unique compared with many other medical and nutritional problems, due to not only having a deeply complex physiological cause, but also a multifactorial environmental, economic and psychosocial origin. Furthermore, PEM is often underdiagnosed and/or overlooked in the presence of similar conditions such as sarcopenia (age-related loss of muscle mass and physical function) and cachexia (loss of muscle mass due to disease-related increases in proinflammatory cytokines and a prolonged acute phase protein response) (7). Beyond the economic consequences of PEM, the high prevalence is significant for the individual, who may experience broad health problems such as decreased cardiac, respiratory, hepatic, and immune function; decreased quality of life; and a significantly increased risk of hospitalisation, institutionalisation and mortality (6, 12). Therefore, a renewed examination of what we have learned about the complex aetiology of PEM over the past 40 years and its implications for practice may be useful in helping to prevent and manage this long-term geriatric syndrome across the continuum of care.