Honesty is one of the bedrocks of medicine—a principle that not only defines ethical practice but also strengthens the doctor–patient relationship. Understanding what honesty means in a clinical setting, and how it shapes trust, is essential to delivering quality care. This chapter explores how honesty supports patient trust and autonomy, underpins informed consent, and fosters shared decision-making. In the collaborative environment of healthcare, honesty is also critical for sustaining effective teamwork—where even small miscommunications can lead to serious errors. We also examine the Canadian Disclosure Guidelines and the Massachusetts Coalition for the Prevention of Medical Error framework, both of which offer clear guidance on how physicians and healthcare providers should communicate with patients when errors occur and harm results.