The birds in this family are medium to large-sized wading birds. They are usually found in dry, tropical habitats in Africa, Europe, South America, Asia, and Australia.

One species that breeds in North America, the double-striped thick-knee (Burhinus bistriatus), is found from southern Mexico south to northern Brazil.

Thick-knees have long legs with large knee joints, strong yellow or black bills, and large, round yellow eyes. They are speckled sandy-brown with white undersides.

Thick-knees are mostly nocturnal. During the heat of the day, they stay hidden under bushes. At night, they can be identified by their distinctive wailing calls. They eat insects and other invertebrates; some species will also eat small mammals and lizards.

Species include the Eurasian thick-knee, the great thick-knee, the Senegal thick-knee, and the Peruvian thick-knee.