Neutron diffraction measurements on Li-6/Li-7 isotopically substituted 10 and 33 mol % *LiTFSA (lithium bis-(trifluoromethylsulfonyl)amide)-AN-d(3) (acetonitrile-d(3)) and 10 and 33 mol % LiTFSA-DMF-d(7)(N,N-dimethylformamide-d(7)) solutions have been carried out in order to obtain structural insights on the first solvation shell of Li+ in highly concentrated organic solutions. Structural parameters concerning the local structure around Li+ have been determined from the least squares fitting analysis of the first-order difference function derived from the difference between carefully normalized scattering cross sections observed for Li-6-enriched and natural abundance solutions. In 10 mol % LiTFSA-AN-d(3) solution, 3.25 +/- 0.04 AN molecules are coordinated to Li+ with a intermolecular LitN(AN) distance of 2.051 +/- 0.007 angstrom. It has been revealed that 1.67 +/- 0.07 AN molecules and 2.00 +/- 0.01 TFSA(-) are involved in the first solvation shell of Li+ in the 33 mol % LiTFSA-AN solution. The nearest neighbor Li+center dot center dot center dot N-AN and Li+center dot center dot center dot O-TFSA(-) distances are obtained to be r(Li+center dot center dot center dot N) = 2.09 +/- 0.01 angstrom and r(Li+center dot center dot center dot O) = 1.88 +/- 0.01 angstrom, respectively. The first solvation shell of Li+ in the 10 mol % LiTFSA-DMF-d(7) solutions contains 3.4 +/- 0.1 DMF molecules with an intermolecular Li+center dot center dot center dot O(DAM )distance of 1.95 +/- 0.02 angstrom. In highly concentrated 33 mol % LiTFSA-DMF-d(7) solutions, there are 1.3 +/- 0.2 DMF molecules and 3.2 +/- 0.2 TFSA(-) in the first solvation shell of Li+ with intermolecular distances of r(Li+center dot center dot center dot O-DMF) = 1.90 +/- 0.02 angstrom and r(Li+center dot center dot center dot O-TFSA) = 2.01 +/- 0.01 angstrom, respectively. The Li+center dot center dot center dot TFSA(-) contact ion pair stably exists in highly concentrated 33 mol % LiTFSA-AN and -DMF solutions.