This chapter provides an accessible introductory view of pre-editing and post-editing as the starting-point for research or work in the language industry. It describes source text pre-editing and machine translation post-editing from an industrial as well as academic point of view. In the last ten to fifteen years, there has been a considerable growth in the number of studies and publications dealing with pre-editing, and especially post-editing, that have helped researchers and the industry to understand the impact machine translation technology has on translators’ output and their working environment. This interest is likely to continue in view of the recent developments in neural machine translation and artificial intelligence. Although the latest technology has taken a considerable leap forward, the existing body of work should not be disregarded as it has defined clear research lines and methods, as it is more necessary than ever to look at data in their appropriate context and avoid generalizing in the vast and diverse territory of human and machine translation.