An academic book chapter should be between 3500-7000 words and focus on a specific research theme or perspective to provide expertise beyond what is found in journal articles. It should include an engaging introduction, main body with informative paragraphs, and a summary. The chapter structure also needs a title, transition to the next chapter, and may use examples, data, or graphics. Writing book chapters can establish credibility as an expert and allow expanding on topics previously discussed in journals.