A laboratory instrument for the preparation of samples includes a base housing with a work compartment enclosed by protective walls, at least one multifunctional work head having the ability to turn about a rotary axis pivotally supported on the base housing. At least two defined functional positions that can be aligned with at least one container platform which is arranged in the work compartment. The first functional position contains a receiving device which serves to hold a dosage-dispensing device with free-flowing dosage material, and each of the other functional positions contains an additional device. At least one of the protective walls has a cutout opening, and the at least one multifunctional work head is arranged partially in the cutout, so that portions of the at least one multifunctional work head lies both inside and outside of the work compartment.