A graphical user interface for a concurrent computing environment that presents the output generated by multiple concurrent computing units during and upon completion of their portions of a concurrent computing computation is discussed. The output from each concurrent computing unit may be directed to a single display where it is portioned into different regions of the display. The output from all of the concurrent computing units or a subset of the concurrent computing units may be shown in different arrangements. Blocks or lines of output from different concurrent computing units may appear in order of arrival at the display, or if precise timing references are available, in order of generation by the concurrent computing units. In either case the relative ordering of the outputs may be used to interpret the progress, performance and results of a concurrent computing computation.