Aim. The aim of this study was to explore the point prevalence of malnutrition and the targeting of nutritional interventions in relation to undernutrition risk before and after an intervention. Background. Malnutrition risk and the precision in targeting nutritional treatment are indicators of quality of care. Knowledge regarding the in-hospital prevalence of malnutrition and nutritional treatment is meagre for Iceland. Design. Pre- and postintervention study. Methods. The study was performed during one day in 2006 (March) and one day in 2007 (April). In total, 95 (89%) and 92 (88%) patients agreed to participate. Moderate/high undernutrition risk was defined as the occurrence of at least two of the following: involuntary weight loss, body mass index below limit and eating difficulties according to Minimal Eating Observation Form - Version II. Being overweight was graded based on body mass index. Specific nutritional care actions were recorded. Intervention: A five-point programme for nutrition and eating was implemented. Results. Moderate/high risk for undernutrition was found in 25 and 17% in the two years (ns, not significant). A high body mass index was found in 53 and 54% (ns). The number of patients with a documented body mass index significantly increased between the two surveys (1 and 30%, p-value < 0 center dot 0005). The use of oral supplements increased from 11-40% (p < 0 center dot 0005) and especially among those at no/low undernutrition risk, with ingestion or deglutition difficulties (p < 0 center dot 0005 in both cases) but not among those with appetite and energy problems (ns). Conclusion. Implementing a nutritional programme does not necessarily affect the number of in-patients with malnutrition, but it is likely to increase the precision of nutritional care to some extent. Relevance to clinical practice. Greater efforts need to be taken to increase the precision of nutritional care among patients at moderate/high undernutrition risk and among those with appetite and energy problems.