Despite the complications of TAG biosynthesis in plants (Fig. 5), we were able to simplify the process into the two blocks of reactions — Block A (fatty acid synthesis) and Block B (lipid assembly) (Fig. 6). The use of top-down control analysis [77], allowed us to measure the amount of control in each Block and, hence, be able to predict which Block might be worth up-regulating initially in order to increase oil production. Clearly, this was a much better situation than predicting (guessing) which enzyme activity might be worth targeting. In fact, the latter approach has seldom paid dividends in plant genetic manipu- lation [82].