This picture depicts a top view of a turbulent spot growing by destabilizing the surrounding laminar (vortical) flow. Flow is from left to right. This picture was the first to appear in an archival publication (Journal of Fluid Mechanics, vol. 110, p. 73, 1981) showing the utility of flow visualization via laser-induced fluorescence (LIF), a technique which is now widely used around the world for detailing the anatomy of three-dimensional flow fields.