Galactic winds, due either to massive star formation or to active galactic nuclei, are one of the favored mechanisms necessary to regulate star formation activity and explain several aspects of present-day galaxies. In particular "cold" galactic winds, where the main ejecta are atomic or molecular, enable the cycling of large amounts of matter in and out of galaxies and provide explanation to a number of observations. Our understanding of how gas is launched and how much mass is involved in these winds is, however, rudimentary. I will present observations of the archetypal nuclear starburst galaxy NGC 253 by ALMA and HST, and show how we are starting to decipher the launching processes and mass loss rates in this example of a starburst-driven galaxy wind.
Specifically, I will motivate the importance of the topic and discuss the morphology, mass, and acceleration of material in the molecular outflow. I will also show some spectacular 0.1" resolution images of the starburst, recently delivered by ALMA.