The acceptability to, and feasibility of, guidance counsellors using YouthCHAT to screen New Zealand secondary school students for mental health issues and risky health behaviours was investigated. Participants were eight guidance counsellors using YouthCHAT in two schools. Over eight months, School A implemented a systematic school-wide screening programme, screening 43% of their student body, whereas School B adopted an opportunistic screening approach, screening <1%. Semi-structured interviews were conducted with guidance counsellors, and data were analysed using a general inductive approach. All participants reported YouthCHAT an acceptable tool; however, while it was well used in School A, usage rates were low in School B. With a structured protocol for screening in place, the use of YouthCHAT by guidance counsellors shows promise.