It is widely acknowledged that minority language survival is not possible unless it is supported at school, in the home, and in the wider community. In English-medium schools where Welsh is taught as an academic subject only, the L2 Welsh-learning child’s opportunity to use and hear Welsh is often limited to that context, however it is vital that the Welsh language is supported in the English-medium educational context in order to contribute large numbers to the Welsh Government’s Million Welsh speakers by 2050 campaign. During recent years, Welsh Second Language as a subject in English-medium schools’ standards has been a cause for concern. Consequently, a recent strategy–Incidental Welsh (Davies, 2012), or Cymraeg bob dydd–was introduced across Wales, which implements the use of ‘everyday Welsh’ across the curriculum. Cymraeg bob dydd requires teachers –native speakers and learners alike –to deliver everyday Welsh vocabulary and phrases as part of their subject lesson, whatever the subject of the lesson may be. However, in many cases, reluctant speakers of Welsh or those who have little or no Welsh language skills (other than the ability to deliver a set of words and phrases to their pupils) lack the necessary confidence that is required for the successful implementation of Cymraeg bob dydd. This thesis aims to explore and evaluate the extent in which Cymraeg bob dydd is implemented in English-medium schools in North Wales. The first study of the research shows that Cymraeg bob dydd isnotbeing implemented in English-medium schools as intended, and the use of Welsh is very limited, and in some cases, non-existent. The remainder of the thesis explores possible reasons for this, including teacher confidence in delivering Cymraeg bob dydd and the pupils’ attitudes towards the Welsh language. Together, these studies form the evaluation of the use of Cymraeg bob dydd.