Mindfulness is widely used in modern society as a treatment for psychological symptoms and as a practice to improve well-being. However, in recent years, teachers of Buddhism, which is the root of mindfulness, have expressed concerns that contemporary mindfulness-based interventions lack a clear ethical framework. In this paper, I examine the need for ethics in mindfulness practice, referring to Buddhism and psychological research, in terms of preventing harmful outcomes, promoting the wellbeing of the practitioners themselves, and providing a foundation for practices that end suffering. I conclude that incorporating elements of ethics into mindfulness practice and research may lead to the development of more effective intervention techniques and theoretical models with more explanatory power.