Objective: This study's purpose was to compare the scope of practice of Dutch dental hygienists educated through a two- or three-year curriculum ('old curriculum dental hygienists' [OCDHs]) with that of hygienists educated through a new extended four-year curriculum leading to a bachelor's degree ('new curriculum dental hygienists' [NCDHs]). Methods: In 2005 and 2007, we obtained surveys from 320 OCDHs and the first 67 NCDHs, respectively, in which respondents were asked to complete a questionnaire and score how often they performed certain dental tasks. By means of factor analysis, these tasks were grouped into nine activity groups and 5 remaining single activities. T-tests and Mann-Whitney U-tests were used to compare the scope of practice between OCDHs and NCDHs. Results: NCDHs worked more often in dental offices (instead of being self-employed) and generally worked more hours per week than OCDHs. They performed more often tasks dealing with caries diagnosis and treatment and less often tasks dealing with prevention and periodontology. These differences were statistically significant. However, in dental offices the differences between OCDHs en NCDHs were far less pronounced. In those practices OCDHs performed dental sealants, small corrections of dentures and / or restoration and caries diagnosis during dental checkup no less frequently than NCDHs. Conclusions: Although prevention remains the core domain (or role) of all Dutch dental hygienists surveyed, the scope of practice substantially differed. This, however, depended not only on education, but also on type of practice. The new curriculum answers to and legitimates an already developed practice of task delegation.