A system and method for isolating cells, comprising: a substrate having a broad surface; an array comprising a set of wells defined at the broad surface of the substrate, each well including: a base surface, an open surface directly opposing the base surface, defined at the broad surface of the substrate, and configured to receive one of a single cell and a single cluster of cells from a direction perpendicular to the broad surface of the substrate, and a set of channels that fluidly couple each well to at least one adjacent well; wherein the set of wells includes an interior subset and an exterior subset fluidly coupled to and surrounding the interior subset by way of the set of channels; and a fluid delivery module surrounding the array and fluidly coupled to each well in the set of wells.