Abstract: A dental chair comprising a pedestal, a lifting assembly mounted on the pedestal, a parallelogram assembly supported by the lifting assembly, a seat assembly pivotally mounted on the parallelogram assembly, and a backrest assembly pivotally mounted to the seat assembly. The lifting assembly is capable of moving the parallelogram assembly horizontally while simultaneously raising or lowering it, thereby causing the seat and backrest assemblies to move vertically without substantial horizontal motion. The seat assembly is hingedly mounted to the parallelogram assembly and includes a transverse shaft and drive means therefor. Means separately link said shaft to the parallelogram and backrest assemblies, such that rotation of said shaft by its drive means causes simultaneous pivotal motion of the seat and backrest assemblies, thereby permitting adjustment of the seat and backrest of the chair to their most convenient inclinations for a given dental treatment.