Both of your authors are optimists by nature. But we’re also realists. It’s in that spirit that this final part of the book was written. We hope for success, but we plan for failure. This is rational as most efforts to change fail. The majority of company mergers fail to realise their expected value. By February, more than 80% of us have abandoned our new year’s resolutions. To put it mildly, making change is really hard.

Even brilliant solutions to problems, those informed by the right data and a clear-headed understanding of causal relationships, aren’t worth much if you can’t put those solutions into action. In fact, the business and workplace landscape is littered with strategies that failed once organisations tried to execute them. The reasons for such failures vary. Solutions can backfire because the experts or funding needed to execute them turn out to be unavailable or far more significant than everyone expected initially. The decision that everyone agreed on ended up locking your company into a path you are desperate to find a route away from.

In the first three parts of The Decision Maker’s Playbook we’ve talked about how to make smart choices. In this part, we want to share how to make that change stick, to ensure that the good choices that you make today become the winning strategies and change programmes of tomorrow.

Because execution failure is so common, it is vital for decision makers to understand what causes such failure and to master strategies for counter-acting those forces. In this fourth and final part we will examine several such strategies (including real options) and incentive systems that will motivate others to execute a solution you’ve settled on and best practices for implementation.