There is expanding interest in mindfulness-based programs (MBPs) within the mainstream. While there are research gaps, there is empirical evidence for these developments. Implementing new evidence into practice is always complex and difficult. Particular complexities and tensions arise when implementing MBPs in the mainstream. MBPs are emerging out of the confluence of different epistemologies—contemplative teaching and practice, and contemporary Western empiricism and culture. In the process of navigating implementation and integrity, and developing a professional practice context for this emerging field, the diverse influences within this confluence need careful attention and thought. Both contemplative practices, and mainstream institutions and professional practice have well-developed ethical understandings and integrity. MBPs aim to balance fidelity to both. This includes the need to further develop skillful expressions of the underpinning theoretical and philosophical framework for MBPs; to sensitively work with the boundary between mainstream and religious mindfulness; to develop organizational structures which support governance and collaboration; to investigate teacher training, supervision models, and teaching competence; to develop consensus on the ethical frameworks on which mainstream MBPs rests; and to build understanding and work skillfully with barriers to access to MBPs. It is equally important to attend to how these developments are conducted. This includes the need to align with values integral to mindfulness, and to hold longer-term intentions and directions, while taking small, deliberate steps in each moment. The MBP field needs to establish itself as a new professional field and stand on its own integrity.