Dialkylaluminium compounds with bi-functional ligands, [E(CH₂)_xNR₂]^– (x = 2, 3; E = S, NR′) have been prepared, and compared to those that contain [O(CH₂)_xNR₂]^–, in order to investigate the effect of the anionic termini on the structure of the aluminium compounds, [R₂Al{E(CH₂)_xNR′₂}]_n. The reaction of R₂NCH₂CH₂SH·HCl with Li[Al(^tBu)₃Me], formed in situ from Al(^tBu)₃ with MeLi, yields (^tBu)₂Al(SCH₂CH₂NR₂), R = Me 1 and Et 2. Reaction of Al(^tBu)₃ with HN(Me)CH₂CH₂NMe₂ and HN(Me)CH₂CH₂CH₂NMe₂ ultimately yields (^tBu)₂Al[N(Me)CH₂CH₂NMe₂] 3 and (^tBu)₂Al[N(Me)CH₂CH₂CH₂NMe₂] 4, respectively. Reaction of HAl(ⁱBu)₂ with HN(Me)CH₂CH₂NMe₂ yields [(ⁱBu)₂Al{µ-N(Me)CH₂CH₂NMe₂}]₂ 5, while [H₂Al{µ-N(R)CH₂CH₂NMe₂}]₂, R = Me 6 and Et 7, are formed from the reaction of AlH₃(NMe₃) with HN(R)CH₂CH₂NMe₂. The molecular structures of compounds 1, 2, 6 and 7 have been determined by X-ray crystallography. Compounds 1–4 are monomeric with five (1–3) and six (4) membered chelate heterocyclic rings. Compound 5 exists as a monomer/dimer equilibrium in solution, in contrast, compounds 6 and 7 exist as bridged dimers. The formation of monomeric chelate structures for compounds 1 and 2, rather than the bridged dimers found for the alkoxide analogs is due to the relative ligand base strength. However, the formation of monomers in the case of compounds 3 and 4 is found to be due to a combination of the steric bulk of the aluminium alkyl and the geometry at the potentially bridging amide group. These results demonstrate a remote geometric control over the degree of association.