Steier, C. Allézy, A.P. Anders, A. Baptiste, K.M. Buice, E.S. Chow, K. Cutler, G.D. De Santis, S. Donahue, R.J. Duarte, R.M. Filippetto, D. Harkins, J.P. Hellert, T. Johnson, M.J. Jung, J.-Y. Leemann, S.C. Leitner, D. Leitner, M. Luo, T.H. Nishimura, H. Oliver, T. Omolayo, O. Osborn, J.R. Pappas, G.C. Persichelli, S. Placidi, M. Portmann, G.J. Reyes, S. Robin, D. Sannibale, F. Sun, C. Swenson, C.A. Venturini, M. Virostek, S.P. Waldron, W.L. Wallén, E.J. JACoW Publishing Geneva, Switzerland 978-3-95450-207-3 10.18429/JACoW-MEDSI2018-TUPH14 English 53-56 TUPH14 lattice emittance storage-ring vacuum kicker Contribution to a conference proceedings 2018 2018-12 https://doi.org/10.18429/JACoW-MEDSI2018-TUPH14 http://jacow.org/medsi2018/papers/tuph14.pdf The ALS-U conceptual design promises to deliver diffraction limited performance throughout the soft x-ray range by lowering the horizontal emittance to about 70 pm rad resulting in 2-3 orders of brightness increase for soft x-rays compared to the current ALS. The design utilizes a nine bend achromat lattice, with reverse bending magnets and on-axis swap-out injection utilizing an accumulator ring. This paper shows some aspects of the completed conceptual design of the accelerator, as well as some results of the R&D program that has been ongoing for the last years.