The analysis of regional variations in hospital admission rates for Belgium and the Netherlands shows that the available number of hospital beds together with the health status of the population (roughly indicated by age-adjusted mortality rates) are common factors to influence these admissions in spite of the fundamental differences between the health care systems of both countries. Further analysis shows that in Belgium the relative number of providers of ambulatory care (general practitioners, internists, paediatricians and gynaecologists) influences the residual admission coefficients negatively. Policy consequences of these findings are discussed. The recent adaptation of the Belgian Hospital Act that enables closure of existing hospitals for planning reasons is hailed with satisfaction. The importance of Roemer's Law—‘a bed built is a bed filled’—is illustrated once again by this analysis.