Rhinoceros are large herbivores that are adapted for gaining energy from the fermentation of fibrous plant material. In this paper we address issues of oversupplementation of energy (leading to obesity) and minerals (particularly iron in Black rhinoceros Diceros bicornis), outline a diet design that relies on forage as the staple component with a reduction in use of pelleted compound feeds and give suggestions for supplement provision. Acquisition of adequate roughage is probably the most important step in the feeding management of large herbivores and should be regarded and organized accordingly. Ration calculation must be an integral part of diet design to avoid the imbalances that are currently observed, especially in relation to mineral provision. The use of grain or grain products in pelleted compound feeds is largely discouraged.