The prevalence of malnutrition within hospital settings is a major concern to all health care workers. The recent development of a simple screening tool for use in such settings has increased the opportunity to identify at-risk patients in a reasonable time frame during their admission. This paper outlines the implementation of a routine nutrition screening and assessment, performed completely by dietitians, across both acute and rehabilitation settings. Dietitians were able to screen, on average, 72% of eligible patients, which ensured timely dietetic intervention. The routine malnutrition screening and assessment process highlighted differences (P < 0.01) in the rates of malnutrition between the acute wards (range 7 to 14%) and rehabilitation ward (49%). Significant differences between acute and rehabilitation patients were also found within the majority of individual diagnostic groups, including all surgery, fractures, cardiovascular incidents and respiratory illness (P < 0.01). The identification of rates of malnutrition between different wards, diagnoses and institutional settings provides dietetic managers with a sophisticated tool that can assist in the allocation of dietetic resources. This operational framework for routine screening of nutritionally at-risk patients in hospital, enables dietitians to develop patient outcomes and an effective nutrition care model.