Thinking about upgrading to Word 5.0? Thinking about switching to a different word processor? Think about Nisus. Nisus is arguably the most powerful word processor to appear on the Macintosh, and it has features that no other program can even approach. Despite this incredible power, Nisus has some potentially serious flaws for creating complex formal documents. This review uncovers the power and the problems to help you decide which program to use. Part one of three.