This chapter introduces and elaborates a comprehensive framework of principles that define effective AI communication in the emerging post-prompt era. It is structured around six core dimensions—clarity and specificity, context-awareness, feedback and refinement, ethical alignment, cognitive enhancement, and emotional-relational intelligence. Each dimension is examined through a set of actionable principles that guide the design and evaluation of human-AI interaction. These principles include fostering mutual clarity, maintaining continuity across contexts, recognising user emotions, managing disagreement, ensuring ethical alignment, and supporting reasoning and creativity. The chapter illustrates these principles through both current applications and speculative future scenarios, emphasising the need for AI systems that are transparent, adaptive, culturally sensitive, and capable of evolving communication strategies. Together, these principles serve as both a blueprint for developers and a critical lens for users, ensuring that AI communication remains grounded in human values while embracing the complexity of future interaction paradigms.