More than 700 bird species breed in North America, and it was not easy to choose a reasonable number to profile. We aimed to include familiar birds with a variety of fascinating approaches to family life. From tiny hummingbirds to enormous herons and eagles, each species has unique constraints and abilities that determine how and where it can build its nest, find food, deliver it to the young, and educate the new generation. Some of the pleasure in studying birds comes from observing differences among species and pondering the reasons. The more you know about them, the more fun it will be to observe them on your own!