There is wide variation in the provision of home mechanical ventilation (HMV) throughout Europe, but the provision of home mechanical ventilation can also vary within countries. In 2008, the overall prevalence of HMV in Norway was 19.9/100,000, and there were huge regional differences in treatment prevalence. The aim of this study is to find explanations for these differences. We gathered multidisciplinary respondents involved in HMV treatment from five hospitals in five different counties to six focus group conversations to explore respondents' views of their experiences systematically. We based the analysis on grounded theory. We found that uneven distribution of ''enthusiasm'' between hospitals seems to be an important factor in the geographical distribution of HMV. Furthermore, we found that the three subcategories, ''high competence,'' ''spreading competence,'' and ''multidisciplinary collaboration,'' are developed and used systematically in counties with ''enthusiasm.'' This culture is the main category, which might explain the differences, and is described as ''wise enthusiasm.'' The last subcategory is ''individual attitudes'' about HMV among decision-making physicians. The most important factor is most likely the uneven distribution of highly skilled enthusiasm between hospitals. Individual attitudes about HMV among the decision makers may also explain why the provision of HMV varies so widely. Data describing regional differences in the prevalence of HMV within countries is lacking. Further research is needed to identify these differences to ensure equality of provision of HMV.