157 Dealing with moral challenges in treatment for transgender children and adolescents: evaluating the role of moral case deliberation 9 INTRODUCTION Transgender care is being offered to an increasing number of children and adolescents (Aitken et al., 2015; Chen et al., 2016; de Vries & Cohen-Kettenis, 2012; Wood et al., 2013). The incongruence they experience between assigned sex and identified gender is called gender dysphoria (GD) and may be diagnosed according to the DSM-5 when accompanied by distress (American Psychiatric Association, 2013). Children and adolescents with GD are usually treated by a team consisting of child and adolescent psychiatrists and psychologists, (paediatric) endocrinologists, gynaecologists (for fertility advice), and surgeons (for gender-affirmative surgery). In this article, the term ‘adolescent’ refers to children and adolescents in whom puberty has started. The start of puberty is defined as the appearance of Tanner stage 2-3 in boys (G2-3) and Tanner stage 2 in girls (M2). This article uses the term ‘transgender adults/adolescents/children’ to refer to persons diagnosed with GD. Transgender teams base their treatment decisions on internationally recognized clinical guidelines set by professional transgender care associations. In practice, these guidelines are often adapted to local situations (Coleman et al., 2012; Hembree et al., 2017). A Dutch treatment protocol for transgender adolescents, sometimes referred to as ‘the Dutch model’, was the first in the world to explicitly describe medical transgender treatment for young adolescents (Cohen-Kettenis, Steensma, & de Vries, 2011). In the Dutch model, the eligibility criteria for such treatment are: a long history of GD, no psychosocial problems interfering with assessment or treatment, sufficient family or other social support, and the appearance of Tanner stages 2-3 indicating the onset of puberty (de Vries & CohenKettenis, 2012; Delemarre-van de Waal & Cohen-Kettenis, 2006; Kreukels & Cohen-Kettenis, 2011; Shumer & Spack, 2015). Over the years, these eligibility criteria have not changed and are also part of the Standards of Care and Endocrine Society clinical practice guideline (Coleman et al., 2012; Hembree et al., 2017). Also, despite an enormous increase, main characteristics (with the exception of a shift in sex ratio with an overrepresentation of assigned females) of the referrals did not change over the years (Arnoldussen et al., 2020; Arnoldussen et al., 2022b). Mental health is an inseparable part of the clinical care of adolescents in the Netherlands. Besides the possible medical treatment, the clinical care requires an ongoing relationship with a psychologist and/or psychiatrist from the team. In many cases, it will also involve a local mental health specialist. In this article, we use the term ‘gender-affirmative treatment’ which includes the medical gender-affirmative part which is always preceded by assessment, and it is always accompanied by mental health counselling. This counselling consists of regular sessions in which information and advice is provided, and psychological and/or family support is given depending on the individual needs.