The leaves are alternate and simple, with shapes generally elliptic to ovate. The flowers are large and tubular, with five broad petals. Typical habitat is light woodland and thickets. Species in cultivation include Brunfelsia americana ("lady of the night") and Brunfelsia pauciflora. Linnaeus named the genus for early German herbalist Otto Brunfels (1488-1534).
Many members of this genus contain toxic and medicinal alkaloids. Brunfelsia grandiflora is used by curanderos in South America as an additive to ayahuasca and contains the psychoactive alkaloid scopoletin. Brunfelsia hopeana contains the alkaloid hopeanine.