AbstractThis paper focuses on conditions that are crucial for the use of Information and Communication Technology (ICT) in the classroom. Particular attention is given to teachers’ tolerance of uncertainty, which is seen as an important internal resource for coping with professional requirements. Furthermore, the paper examines whether teachers’ tolerance of uncertainty is related to other internal resources (positive views on ICT, ICT-related self-efficacy) and external resources (ICT-related teacher collaboration). The data are derived from a survey among 8th grade teachers in secondary schools in Germany conducted as part of the IEA International Computer and Information Literacy Study (ICILS 2018). The findings show a positive relationship between teachers’ tolerance of uncertainty and their use of ICT in the classroom. Teachers’ tolerance of uncertainty is furthermore in particular positively related to teachers’ positive views on ICT and ICT-related teacher collaboration at school. The relationship between teachers’ tolerance of uncertainty and their use of ICT in the classroom remained when statistically controlled for internal and external resources. Teachers’ tolerance of uncertainty can therefore be seen as a resource in the teaching profession.