Abstract: The up-down element of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix, V_ud, dominates the top-row sum, and with a fractional uncertainty of 0.021%, it is the most precisely known value in the CKM matrix. The determination of this quantity relies nearly entirely on high-precision superallowed beta-decay ft value measurements and their associated theoretical corrections. For more than a decade, the top-row sum has been consistent with the Standard Model prediction of unity, with the limiting uncertainty being the inner radiative correction that is applied to the superallowed data. Very recently, a new evaluation of this theoretical quantity resulted in a shift in the central value as well as a reduction in its uncertainty. This new result presents a problem to the Standard Model, as it now generates a 4-sigma tension with the top-row unitarity constraint, and leaves V_us as the limiting factor on CKM tests.  In this seminar, I will present a history of how we got to this point and where we are going, and discuss which few measurements for the extraction of V_ud are still relevant to the advancement of this field.