A comprehensive guide to the speculative sub-genre of alternate history fiction, this book maps the unique terrain of this vibrant mode of storytelling and then explains how to write it. First giving a concise conceptual overview and the critical tools to differentiate the different forms of counterfactual fiction, Jack Dann lays out the 'tricks of the trade' such 'Heinleining', how to create recognizable 'divergent points' and how to employ paratextual elements and 'layering' to overcome readers' unfamiliarity with invented counterfactual events and cultures. Alongside this, Dann takes you step-by-step through a complete short story to demonstrate, line-by-line, how alternative history fiction works. As well as Dann's exacting methodology for writing professional quality alternate history stories, this book also features a live-on-the-page Q&A with some of the most esteemed alternate history writers working today, including Kim Stanley Robinson, John Birmingham and Lisa Goldstein among many others, who will detail their own particular hacks, theories, processes, methods and strategies. Combining extensive and deep knowledge of the field with accessible writing advice, this is the ultimate guidebook to the broad and complex sub-genre of counterfactual and alterative history fiction.