The aim of this study was to use a decision tree analysis, to determine which bowler types were most successful within a T20 cricket match in English domestic cricket. Five seasons of data were used to establish a significant sample, representing the English domestic game in full. Success probabilities were calculated for each bowler type, and were established within certain scenarios, including Home vs Away, 1st or 2nd innings, the strength of opposition, the over being bowled, and the handedness and strength of the batter. Spin bowlers were proven to be significantly strong throughout each scenario and the entire sample, while left-arm seam bowlers also proved to be a useful commodity to have within a bowling line-up. Left-arm Chinaman bowlers proved to be by far the most successful, however exceptionally underrepresented within the sample, and should looked to be developed within the English county system.