It took centuries of work by many collaborators, working together and independently, to identify and understand the basic building block of all life—the cell—and develop a scientific theory to explain its functions. That a unified theory could emerge from such divergent sources and beliefs is a tribute to the discipline of science. It is also evidence of the researchers’ determination to understand what a cell is and how it works. From Hippocrates (born in 460 B.C.) to the Human Genome Project (completed in 2003), the men and microscopes that made possible exploration and development of the Cell Theory, a foundation of modern biology, are presented. The succinct text is supported by color photographs and dynamic graphics. Sidebars, offset in contrasting colors, add relevant details to each page. A two-page spread at the end lists the contributions of women researchers, who with rare exceptions were only allowed to be active in the scientific community since the nineteenth century. This addition to the “Shaping Modern Science” series closes with a timeline, a glossary, a list of books and websites titled “For More Information,” and an index. It would be a good addition to a middle school or high school science class or library. Reviewer: Hazel Buys