In 2003, in response to a series of malaria fatalities among employees during the previous 18 months, an oilfield services company launched a Malaria Prevention Program aimed at protecting employees and their families mostly in sub-Saharan Africa, where the malaria risk is highest (Barbey et al., 2006). The program has proved effective in reducing malaria incidence and fatalities within the company—from four in the preceding two-year period to two over the past six years. While the program has been effective and continual improvements to the various elements of the program have been made during the six years of implementation, it has also suffered setbacks from the merely undesirable to the catastrophic. This paper explores how it became necessary to recalibrate the program, with a continued focus on behavior change and introduction of additional stringent procedures. Both individual and management accountability are emphasized as a strategy for sustained effectiveness.