As with many edited volumes that have numerous contributors, I think some chapters are stronger than others, and there are certainly some I significantly disagree with. If it were up to me, the volume might have included more focus on some issues, and less on others. For example, I would have included more material on the role of ignorance in warfare. The editors themselves note that the volume only briefly touches on ignorance in legal theory and the administration of judicial systems. The realm of ignorance is so vast that no one volume can fully cover all of it. But this one probably comes closer to doing so than any other published in recent decades.
My own contribution to the volume deals with the phenomenon of rational ignorance – situations where people make rational choices to forego acquiring knowledge that is potentially available to them. My previous work on rational ignorance focuses primarily on voter ignorance, which I argue is often dangerous. But in the Handbook chapter, I emphasize that in many situations, rational ignorance is actually beneficial. If people always learned the maximum possible amount of knowledge, they would pass up opportunities to use the same resources for more valuable purposes. Still, the chapter also emphasizes how rational ignorance can be harmful in situations where individually rational behavior can lead to bad collective outcomes. For example, it is often rational for individual for voters to be ignorant about politics; but an entire electorate of mostly ignorant voters can be a real menace. The chapter also explains why rational behavior (including rational ignorance) isn’t necessarily morally right, and how rational ignorance differs from irrational ignorance and what I call “inadvertent” ignorance.
Because of its exorbitant cost (priced for the academic market), I don’t necessarily recommend that you buy the Handbook, unless you have an expense account, are very wealthy, or are an academic library. But if you are doing research related to ignorance or are just interested in the subject, this is a book you may well want to take a look at.