No / This paper presents findings from a study of 55 cases of decision implementation. The research identifies a number of features that characterize the way implementation is managed which appear to enhance the chance of success. Analysis reveals patterns in the data indicating that these features fall into two groupings, giving rise to two distinct approaches to implementation management. These are termed the Experience-based approach and the Readiness-based approach from the initial conditions which give rise to each. Although following either approach may enhance decision performance, the greatest success is associated with a dual approach. Implementations that follow neither are generally less successful. A theory of implementation management is postulated, comprising a Planned Option and a Prioritized Option.