The first systematic study of the intramolecular alpha-effect, both in the stable ground-state structures and in the high-energy intermediates, was accomplished using the anomeric effect as an internal stereoelectronic probe. Contrary to the expectations based on the simple orbital mixing model, the lone pairs in a pair of neutral directly connected heteroatoms are not raised in energy to become stronger donors toward adjacent alpha- and pi-acceptors. Instead, the key n((x-y))->sigma(C-F)* interactions (X,Y = 0,N) in the "alpha-systems" (both acyclic and constrained within a heterocyclohexane frame) are weaker than n(x)->sigma(C-F)* interactions in "normal" systems. Surprisingly, polar solvent effects increase the apparent magnitude of alpha-effect as measured via increase in the opposite to the solvent dependence of normal systems where the anomeric effect is severely weakened by polar solvents. This contrasting behavior reflects the different balance of electrostatic and conjugative interactions in the two types of anomeric systems: the alpha-systems suffer less from the unfavorable orientation of bond dipoles in the equatorial conformer, a destabilizing electrostatic effect that is shielded by the polar environments. A weak alpha-effect is brought to life when the buttressing alpha-heteroatom bears a negative charge. However, electrostatic components mask the role of stabilizing orbital interactions. In contrast, the increased electron demand in carbocations and related electron-deficient TS- like structures does not lead to activation of the alpha-effect. As a consequence, we Observed that ethers are better radical- and cation-stabilizing groups than peroxides. The latter finding should have significant implications for understanding the mechanistic complexity associated with the interaction of carbonyl compounds with hydroperoxides and H2O2 in acidic media, as such reactions involve alpha-cationic intermediates. anomeric stabilization. This behavior is