I have focused my entire career on the human immune system in health and disease, with a particular interest in cytokines, B lymphocytes, and dendritic cells (DCs). Our work on DCs grew out of our discovery that GM-CSF enables the generation of large numbers of DCs from CD34+ hematopoietic stem and progenitor cells. That finding launched a nearly three-decade focus on DC biology, alongside a two-decade collaboration and friendship with Ralph. In this presentation, given in honor of Ralph, I will summarize the salient points of that journey. I will close with our latest data, generated with Duygu Ucar at JAX-GM, on the balance of Th10 and Tfr cells in older adults responding — or not — to the influenza vaccine.