Annual or perennial herbs with radical and alternate or spiral leaves (Knowltonia, Ranunculus and Thalictrum), or shrublets or woody climbers with opposite or whorled leaves (Clematis (including Clematopsis)). Stipules present or 0. Leaves simple or compound. Inflorescences usually terminal and 1-many-flowered. Flowers hypogynous, usually bisexual and actinomorphic; sometimes polygamous or dioecious. Sepals free, often petaloid. Petals free, sometimes 0. Stamens numerous. Carpels 1-many, usually free. Fruit usually composed of 1 or more follicles or a cluster of achenes.