Donald A. Ritchie, a congressional historian for forty years , takes readers on a fascinating, behind-the-scenes tour of Capitol Hill, pointing out the key players, explaining their behavior, and translating parliamentary language into plain English. He also explores the essential necessity of compromise to accomplish anything significant in the legislative arena. However, recent events show that political polarization has hardened and produced gridlock, as Ritchie explains in this new edition. The 2020 election also produced a more diverse membership in terms of gender, ethnicity, religion, and ideology, with primary elections resulting in the defeat of moderate candidates by opponents ranging from socialists on the left to conspiracy theorists on the right, making bipartisan compromise harder to achieve. Among the most significant events since the last edition, the Senate ignored President Obama's last nomination to the Supreme Court and then adopted a nuclear option to streamline future Supreme Court confirmations. The House also twice impeached President Trump, processes that starkly expose the differences between the majority-rule requirements of the House and the super-majority requirements of the Senate. This new edition explains how the parties have changed in light of the unprecedented politics of the past four years, culminating in the mob attack on the U.S. Capitol on January 6, 2021, and how this development has affected both the House and the Senate.