A large family, present in both temperate and tropical parts of the world. Like the two families preceding, the pod is a common form of fruit, but it is less often woody than in the Caesalpiniaceae, and less often found in bunches than in the Mimosaceae. In West Africa, there are few tree species, but climbers, shrubs and especially undershrubs as well as herbs are common.

Mainly food and fodder species have been introduced, but the decorative species include several American and Asiatic species of Erythrina, Clitoria and Pueraria. Madre (Gliricidia sepium), from the West Indies, is popular as a hedge plant, as well as being useful for yam sticks.

Members of the family may be recognised by their alternate, stipulate compound leaves, which are often glandular and possess both pulvini and pulvinules. Leaflets are conduplicate and have stipels in about two-thirds of genera, but they often fall early and immature leaves must be examined. Stylosanthes erecta, a common seashore shrub, lacks stipels, as do several genera with paripinnate leaves (marked with an asterisk below). The flowers, described as ‘papilionaceous’, are distinctly zygomorphic, with the adaxial petal outside its neighbours. Nine of the 10 stamens are frequently joined in an abaxial trough, the tenth adaxial (vexillary) stamen, opposite the standard (vexilla) being free.

Compound imparipinnate or digitately trifoliolate leaves are common, but, although unifoliolate, compound paripinnate and digitate leaves are less common, they occur in so many genera as to be useless on their own for the purposes of identification.