This book is about the implications of constructivism for instructional design practices, and more importantly, it is about a dialogue between instructional developers and learning theorists. Working with colleagues in each discipline, the editors were amazed to find a general lack of familiarity with each others' work. From an instructional design perspective, it seems that the practice of instructional design must be based on some conception of how people learn and what it means to learn. From a learning theory perspective, it seems obvious that the value of learning theory rests in the ability to predict the impact of alternative learning environments or instructional practices on what is learned. Thus the interchange of ideas between these disciplines is essential. As a consequence of both the information rich environment and the technological capability, business is seen moving away from a fixed curriculum and toward providing information and instruction when it is needed. These changes bring about a window of opportunity establishing a dialogue that will provide for a richer understanding of learning and the instructional environment required to achieve that learning. The editors hope that this book is the beginning of the conversation and that it will serve to spur continued conversation between those involved in learning theory and those involved in the design of instruction.