This Work Examines Changes In Voters' Electoral Choices Over Time And Investigates How These Changes Are Linked To A Growth In Instability. Ruth Dassonneville's Core Argument, Supported By Extensive Empirical Data, Is That It Is Group-based Cross-pressures That Lead To Instability In Voters' Choices. Ruth Dassonneville. Also Issued In Print: 2022. Includes Bibliographical References And Index.