This lecture by Prof. Ali Abur discusses the challenges of state estimation in large power grids, focusing on avoiding complete divergence of state estimators. The presentation covers the state estimation problem, errors leading to convergence failure, previous work on convergence, leveraging earlier work on multi-area state estimation, and the use of recursive partitioning to address divergence. The lecture concludes with a summary of the developed software's capabilities and testing results using IEEE test systems and real utility system cases.