Life insurance is a mature business, and profitability in many markets is still below pre-crisis level. Making the most of the in-force book can unlock substantial value: 7-10 bps of the reserves in additional operating profit, and potentially much more if effective in-force management becomes part of business as usual. In this paper, Oliver Wyman examines the sources of in-force optimization and outlines the five guiding principles to seize this opportunity.