NEt3 and Me3NCH3CH2NMe2 were converted with C12H25Br and Me2NC12H25 was converted with NH2(CH2)(n)NH2 (n = 3,4 and 6) to 5 resp. quaternary salts. The products were used as cationic surfactants and studied for crit. micelle concn. (CMC) and surface tension in their aq. solns. The gemini surfactants showed lower CMC than the single ones.