Over the last number of years, there has been an increased move towards attending to the social and emotional wellbeing of students in Irish post-primary schools. Several studies have indicated that educators' positive attitudes toward health and wellbeing education are crucial to achieving whole-school implementation in terms of the promotion of student wellbeing. However, as of yet, no test instrument exists that is designed to quantify the attitudes of educators in this regard. This study aimed to develop a test instrument that could be used to assess educators' attitudes with regard to the promotion of student wellbeing in Irish post-primary schools. The study was conducted in three stages: Content validity, involving seven experts and 14 educators; exploratory factor analysis (n = 129), and; confirmatory factor analysis (n = 99). Analyses indicated the viability of a 10-item two-factor model, which was named the 'Attitudes Toward Wellbeing Promotion' (ATWP) scale.