Several other angiosperm families once thought to be related to the Solanaceae are now considered part of it. These families include:
- Nolanaceae (Nolana);
- Goetzeaceae (Goetzea, Henoonia, Espadaea, Coeloneurum);
- Duckeodendraceae (Duckeodendron);
- Sclerophylacaceae (Sclerophylax).
Advances in the understanding of the phylogeny and relationships of the family have largely come through the use of molecular markers. These studies have highlighted some surprising relationships that are quite different from those traditionally accepted by past taxonomists.