Both interphasic water/organic solvent transfer and transport through liquid membranes may be influenced to a certain extent by several physicochemical factors like the structure of the ligand, the nature of the cation, the type of the anion (acting as a counterion), the interfaces thermodynamic equilibria, and the nature of the membrane solvent. The effects of these factors upon both the transfer and the transport through liquid membranes of complexes of some amino acids (L-tryptophane, L-methionine, L-phenylalanine, L-leucine, L-isoleucine, and L-valine) and amines (methylamine, dimethylamine, and n-propylamine) in cationic forms with various macrocyclic ligands (18-crown-6, benzo-18-crown-6, and dibenzo-18-crown-6) have been investigated.