In this presentation, we study various ways of organising education for mentors in Estonia, Denmark, Finland, Sweden and Norway. Our research questions are: (1.) How have the mentor training programmes been carried out? (2.) What is the degree of formalization of mentor’s education in the participant countries of NQT-COME? (3.) What are the advantages and disadvantages of formalizing mentoring and mentor education? Firstly, we will parallelly introduce a general description of the national solutions of education for mentors from seven viewpoints: (1.) by whom are the who mentors’ education organized (2.) what are the aims, contents and structures of mentor studies (3.) what is the level of accreditation of studies (4.) how is the mentors’ training financed (5.) how is it connected with initial and in-service teacher education (6.) how are the mentors recruited (7.) what are the current challenges and further plans in each of the aforementioned countries. Drawing from this, we will closer analyze the various national solutions within a continuum of formalization vs. in/nonformalization. As a conclusion, the most formalized system is one implemented in Estonia, whereas the least formalized practice architecture is found in Finland.