The abstract of the manuscript reads as follows: ‘Inquiry-based science education is an important innovation. Researchers and teachers consider it to be stimulating for pupils’ application of research skills, construction of meaning and acquiring scientific knowledge. However, there is ambiguity as to what competencies are required to teach inquiry-based science. Our purpose is to develop a profile of professional competence, required for effective inquiry-based science teaching in primary schools in the Netherlands.  This article reviews literature and compares the outcomes to the American National Science Education Standards (NSES).  In so doing it seeks to answer the following research questions: What elements of competencies required by primary school teachers who teach inquiry-based science are mentioned, discussed and researched in recent literature?; To what extent are the American NSES (introduced 15 years ago) consistent with elements of competencies found in recent literature? A comprehensive literature review was conducted using ERIC and Google Scholar databases. Fifty-seven peer-reviewed scientific journal articles from 2004-2011 were found using key word combinations. Analysis of these articles resulted in the identification and classification of 22 elements of competencies.  This outcome was compared to the American NSES, revealing gaps in the standards with respect to a lack of focus on how teachers view science teaching and themselves as teachers. We also found that elements of competencies are connected and poor mastery of one may affect a teacher’s mastery of another. Therefore, we propose that standards for the Netherlands should be presented in a non-linear, holistic, competence-based model.’