Group technology exploits similarities in product and process design to effectively meet the diversity of customer demand. In this paper we consider one of the implementations of this concept-heuristics for family based dispatching. Intrinsic to family based dispatching is the grouping of similar types of products for joint processing. Hence, the number of set-ups may be reduced. Consequently, lead time performance of the shop can be improved. Unfortunately, variances of processing and set-up times-as found in practice-have received little attention in heuristics' construction and testing. To address this issue we propose several new, non-exhaustive heuristics. Whereas existing exhaustive heuristics set batch contents equal to all products ...