A family of tropical and subtropical trees, shrubs and tendril lianes with, in West Africa, three species of these last representing large American genera – Cardiospermum spp. (balloon vines) and Paullinia pinnata.

Members of the family may be recognised by their alternate, compound pinnate leaves with conduplicate leaflets, and cymose spike or panicle-like inflorescences of minute, pale, apparently flowers. The petals bear scales or hairs on their inner faces, and there is an annular extrastaminal disc, or the disc or disc glands stand to one side of the stamens and pistil. The fruits are often three-valved capsules, with a single arilloid seed in each cell. Tissues are generally soapy when crushed in water.

The climbers have paired inflorescence tendrils and imparipinnate stipulate leaves, while the trees and shrubs have paripinnate exstipulate leaves, in which the rachis is often slightly prolonged. There is rarely only one pair of such leaflets (Aphania). The leaflets commonly decrease in size towards the base of the leaf, and the lowest pair may arise next to the axil (the leaf being ± sessile), and form pseudostipules (Eriocoelum, Blighia, compare Bignoniaceae).

There are 1–3-foliolate leaves in the genus Allophylus and 1-foliolate leaves only in Dodonaea viscosa, in both cases the leaves being exstipulate. D. viscosa is a glandular sea coast shrub with ⊕ apetalous four-part flowers.

The habit of a small erect palm is characteristic of some under-storey species of Chytranthus, Deinbollia and of Radlkofera calodendron.