the methodology applied in this study. Despite its coherency, this mechanism cannot be applied to hydrogermylation since its occurrence would result in the formation of Markovnikov products. Instead, the reaction pathway that should be discussed (Chart 3), proceeds after sodium dihydro(phenyl)germanide VII is formed. This species attacks a styrene molecule at the terminal carbon atom and produces a carbanion (IX-XI). The latter is again a secondary, resonance-stabilized one. This time, however, the germanium atom is at the anti-Markovnikov position. The final product XV is released after this carbanion abstracts a hydrogen cation from phenylgermane (XII-XIV) and regenerates sodium dihydro(phenyl)germanide for the next cycle. The analysis of Chart 3 delivers a precise explanation for the anti-Markovnikov mode of reaction between phenylgermane and styrene. Starting from V, a barrier of only ca. 11.5 kcal/mol (VI) has to be overcome to generate NaPhGeH2 (VII). This step can be seen as essentially irreversible as the reverse reaction would require ca. 30 kcal/mol. The cycle itself includes two transition states: a relative 16.5 kcal/mol one of styrene activation X, and a 13 kcal/mol one of sodium dihydro(phenyl)germanide regeneration XIII. the former is much lower than activation of styrene by NaHBMe3 (23 kcal/mol) and provides a convincing explanation for the anti-Markovnikov mode of reaction. Gibbs free energy profiles display similar features for diphenylgermane (for details, see SI). The mode of initial generation of the essential sodium dihydro(phenyl)germanide has found further support in an experiment showing that increase in the amount of NaHB(sec-Bu)3 resulted in proportional increase of the amount of ethylbenzene formed. Altogether, we have demonstrated that sodium tri(sec-butyl)borohydride is a good initiator of anti-Markovnikov selective hydrogermylation of conjugated aromatic alkenes. It is not, however, a catalyst of this process, since the reaction proceeds via a germanide anion, which is regenerated in the last step, and no borohydride moiety is further needed. This can result in the conclusion that hydrogermylation in this reaction system can be seen as a 'living' process.