Herbs, stemsucculents or woody plants, sometimes with phylloclades, often containing lactiferous juice. Leaves mostly alternate, rarely opposite or verticillate, simple or compound. Stipules mostly present and sometimes with stipellae. Extrafloral nectaries often present. Indumentum various. Inflorescence various, the main branching often racemose, the following cymose. Flowers monoecious or dioecious, when monoecious the inflorescence of either male or female flowers or inflorescence of female flowers in the lower and male flowers in the upper portion; in Euphorbia and related genera the inflorescence a cyathium. Flowers with sepals and petals, the petals often reduced or wanting or the flowers naked. Disk often present, various in shape, in the male flowers either intrastaminal or extrastaminal. Stamens as many or twice as many as the sepals or numerous or reduced in number to only one; filaments mostly free. In the male flower a rudiment of the ovary often present. Ovary 3-locular, rarely 2—many-locular. In the female flower sometimes staminodia present. Styles usually 3, free or connate, often 2-partite. Ovules 1—2 in each locule, anatropous or epitropous, often provided with an obturator and a caruncula. Fruit mostly schizocarpous, the cocci opening by 2 valves, rarely a drupe or a berry. Seeds with endosperm. Embryo with broad cotyledons. About 7500 species in 300 genera, worldwide but especially in the tropics.