This article proposes that there exist "glass doors" impeding men from entering and participating in ECEC work. Across developed countries, men's participation as carers and teachers in early childhood education and care (ECEC) services tends to be viewed as highly desirable and much has been written about the importance of men in ECEC. However, the proportion of men has not yet risen to a level that effectively challenges the near absence of gender diversity in the sector. How could this be when there are no formal legal or other visible barriers preventing men from entering the early childhood profession? To explore why it has proven difficult to make much headway in increasing the proportion of men in ECEC we reviewed and discussed the scientific literature and in particular drew on research and experience from our own countries--Austria and New Zealand. This led to the generation of six descriptions for what we found to be the main "glass doors". In practice the glass doors are unseen or invisible. These are rarely acknowledged and not known until they are walked into but these are real barriers to men being able to participate equally with women in ECEC.