Superconformal electrodeposition processes enable void- and seam-free metal filling of high aspect ratio features from tens of nanometers to hundreds of micrometers in size. There are two known mechanisms underlying such processes: Curvature Enhanced Accelerator Coverage (CEAC) and S-shaped Negative Differential Resistance (S-NDR). Voltammetric measurements on planar substrates can quantify kinetics in models based on both mechanisms, enabling accurate, a-priori prediction of filling from a particular electrolyte in a particular size and aspect ratio feature. I will summarize the chemistries and associated mechanisms for superconformal Cu, Ag, Au, Co, and Ni feature filling, including experiment and model predictions, for processes that are drop-in compatible with those presently used for fabrication of Cu damascene and through silicon via interconnects.