Abstract
There is a wide variety of data, both static and streaming, being published on and about computing Grids. However one aspect of Grid data that has received relatively little attention thus far is that of incompleteness. With potentially many data sources available to choose from, each with its own limitations in terms of coverage of data sets and of overall reliability, there are many opportunities for inaccuracy due to incompleteness in the data. In this short paper different types of incompleteness are identified in the context of R-GMA as part of an ongoing research project aimed at finding solutions to some of these.