AbstractWe present Gemini/IFU observations that sample the roots of the galactic wind outflows in the starburst galaxies NGC 1569 and M82. The good spatial and spectral resolutions of these observations allow us to probe the interactions of cluster winds with their environments on small scales. For both galaxies, we find a ubiquitous broad (200–300 km s⁻¹) Hα component underlying a brighter narrower component. By mapping the properties of the individual line components, we find correlations that suggest that the broad component results from powerful cluster wind-gas clump interactions. For NGC 1569, there is little evidence for organised gas flows within the central zone and we suggest that the flow-dominated wind must form well beyond the region containing the massive star clusters. For M82, we find that the kinematics of the wind base are very complex; the width of the broad component reaches values of > 350 km s⁻¹ at the base of the wind, and the outflow itself rapidly becomes chaotic in the inner wind region.