Hemenway, a permaculture expert and associate editor of The Permaculture Activist, explains how gardens can function as ecosystems, describes the basic parts of an ecological garden (soil, water, plants, and animals), and shows how to create backyard ecosystems through guilds. Guilds, the author tells us, are groups of plants that function as an ecosystem to provide products for humans, create cover and food for wildlife, nourish the soil, conserve water, and repel pests. A simple example of a guild is the "three sisters" (corn, beans, and squash); corn stalks provide a trellis for beans, the beans supply nitrogen to the soil, and the squash leaves inhibit weeds and conserve water. While Hemenway's ideas are intriguing, creating guilds specific to an area involves extensive research, which involves either observing plant communities in the wild or using books or university contacts. In addition, the author doesn't sufficiently explain how to incorporate the many sun-loving vegetables and flowers into guilds, which are often shade-oriented. Recommended only for botanical and academic libraries. Sue O'Brien