The paper explores issues related to prisoners’ Christian conversion experiences in the Chinese context of Hong Kong: How common are conversions? What motivates them? How are they experienced? What impacts do they have? How sustainable are they and how are they to be understood? The paper works through quantitative and qualitative steps: Quantitatively, it surveys the frequency, motives, and subjective experiences of prisoners’ conversions. Through extended interviews with a small number of inmates and former inmates, the paper investigates subjective experiences of transformation and establishes factors that help to sustain conversions. Finally, the paper considers the consequences for pastoral ministry with people in prison and with ex-inmates.