Building quality work-based learning opportunities for student teachers is a challenge for schools in school-university partnerships. This study focused on the guidance of student teachers by means of a mentoring approach aimed at sharing practical knowledge, with student teachers' learning needs as an emphasis. The approach was built on collaborative lesson planning, enactment, and evaluation. The study followed three triads (student teacher, mentor, school-based teacher educator) and examined participants' appreciation of the effectiveness of the approach and their perception of relevant conditions. The approach was considered effective: deeper conversations appeared and new issues emerged earlier than in regular mentoring conversations. (Contains 1 table.)