Turnovers, or leadership changes, play a central role in political systems and the investment decisions of economic actors across sub-Saharan Africa. In some cases, turnovers have been followed by rapid increases in investment and in others, by decreases. To understand how political turnovers affect investment decisions within neopatrimonial systems, I argue that the characteristics of new leaders must be considered in addition to the processes by which the turnovers took place. Crucially, I argue that investment increases result when new leaders have greater capacity and different ethnic and party affiliations than their predecessors. Political economists analyzing narrow types of turnovers have agreed that they are consequential but differed concerning whether the effects are positive or negative. A comprehensive, causal theory explaining the full range of turnovers and subsequent economic outcomes, including mechanisms, is lacking. To build a theory that addresses this gap, I conduct three case studies of turnover in Madagascar using data from over 100 elite interviews, three focus groups, and multiple databases of contemporary news sources. Based on these case studies I argue that varying investment outcomes following turnover are determined by four types of instability: security, regime, administrative, and network. Security and regime instability accompanying turnover reduce the propensity to invest, network instability increases the propensity to invest, and administrative instability increases investment when it is characterized by higher capacity among incoming executives in comparison to their predecessors. The mechanisms detailed in this dissertation which connect systemic instability to individual investment decisions are narrative creation, uncertainty minimization, and boundary aversion. Following the logic of nested analysis, which positions case studies in relation to large-N analysis so that each can inform the other, I compile a cross-national, time-series dataset of turnovers in independent sub-Saharan Africa with measures that operationalize the components of instability. I then propose two models which seek to capture the extent to which the relationship in Madagascar between turnover and investment applies to Africa generally. Finally, I assess the implications of these findings for the political economy literature, policymakers, political risk professionals, and future research.