PurposeRecent research finds that youth who identify as transgender or gender-expansive are disproportionately incarcerated in juvenile justice systems and are treated differently from their non-trans peers (Himmelstein and Brückner, 2011; Hunt and Moodie-Mills, 2012; Irvine, 2010; Mitchum and Moodie-Mills, 2014). Juvenile justice systems have paid little attention to this group of young people in terms of their unique service needs and risk factors. Using qualitative methods, the researchers analyze in-depth interviews and focus group findings from formerly incarcerated trans youth in juvenile justice settings to better understand their experiences. This paper aims to examine the challenges for young people, and, as well as considered recommendations for juvenile justice professionals to study toward making changes in policies, practices and programs that are needed to support young people who are transgender or gender expansive.Design/methodology/approachUsing qualitative, case examples and descriptive analysis, this paper describes the experiences of trans youth in juvenile justice settings and studies toward developing models of promoting trans-affirming approaches to enhance juvenile justice institutions for trans and gender-expansive youth placed in them. The paper describes the evolution of an approach used by the authors, in New York state juvenile justice settings to increase a trans-affirming perspective as a central role in the organization’s strategy and design, and the methods it is using to institutionalize this critical change. Findings culled from the focus groups and in-depth interviews with 15 former residents of juvenile justice settings and several (3) key staff members from the juvenile justice system, focusing on policies, practices and training models are useful tools for assessing progress and recommending actions to increase the affirming nature of such systems. At its conclusion, this chapter will provide clear outcomes and implications for the development of policies, practices and programs with trans and gender expansive youth in juvenile justice systems.FindingsFinding are conceptualized in six thematic categories, namely, privacy, access to health and mental health care, the difference between sexual orientation and gender identity, name and pronoun use, clothing, appearance and mannerism, and housing issues.Research limitations/implicationsThis study is limited as it focuses on formerly incarcerated youth in the New York City area.Practical implicationsThe following implications for practice stemming from this study are as follows: juvenile justice professionals (including judges, defense attorneys, prosecutors, probation officers and detention staff) must treat – and ensure others treat – all trans and gender-expansive youth with fairness, dignity and respect, including prohibiting any attempts to ridicule or change a youth’s gender identity or expression. Having written nondiscrimination and anti-harassment policy is also essential. These policies can address issues such as prohibiting harassment of youth or staff who are trans or gender expansive, requiring the use of respectful and inclusive language and determining how gender rules (e.g. usage of “male or “female” bathrooms, gender-based room assignments) will be addressed for transgender and gender-nonconforming youth. Programs should also provide clients and staff with training and helpful written materials. Juvenile justice professionals must promote the well-being of transgender youth by allowing them to express their gender identity through choice of clothing, name, hair-style and other means of expression and by ensuring that they have access to appropriate medical care if necessary. Juvenile justice professionals must receive training and resources regarding the unique societal, familial and developmental challenges confronting trans youth and the relevance of these issues to court proceedings. Training must be designed to address the specific professional responsibilities of the audience (i.e. judges, defense attorneys, prosecutors, probation officers and detention staff). Juvenile justice professionals must develop individualized, developmentally appropriate responses to the behavior of each trans youth, tailored to address the specific circumstances of his or her or their life.Social implicationsProviding trans-affirming services to youth in juvenile justice settings is a matter of equity and should be the goal strived for by all systems that care for these young people. Helping trans and gender-expansive youth reenter and reintegrate into society should be a primary goal. There are many organizations and systems that stand ready to assist juvenile justice systems and facilities in supporting trans and gender expansive youth in their custody and helping them to rehabilitate, heal and reenter a society that welcomes their participation and where they can thrive and not just survive.Originality/valueThe paper is original in that it examines the lived experiences of trans and gender-expansive youth in juvenile justice systems. An area, which has not been fully explored in the professional literature.