This chapter will draw on our research looking at international and national best practice in supporting beginning teachers during their Initial Teacher Education and beyond. It will combine research, theory and practical examples to show how relationships are able to positively affect beginning teachers’ development, training and identity as teachers. The importance of relationships for beginning teachers as a mediating factor in their well-being will be highlighted, and we will also explore how these relationships can be positively built on to support beginning teacher and mentor well-being. The concept of the dynamic flux of well-being – where well-being is considered in a state of constant shift or movement – will be introduced in this chapter and will be developed by examining the balance between the challenges beginning teachers (and mentors) experience and the resources they have to support them. The chapter will also consider how positive relationships can mitigate some of the challenges beginning teachers experience, as well as how to develop the resources that both beginning teachers and mentors can draw on to facilitate their well-being.