Density, speed of sound, surface tension, refractive index, and isentropic compressibility of AOT (sodium bis-(2-ethylhexyl) sulfosuccinate) +2,2,4-trimethylpentane + water mixtures have been measured at different temperatures in the range of (5 to 60) degrees C. Mixtures employed in the present paper have a common characteristic based on the value of the W parameter (W = [water]/[AOT]) that remained constant at a value of 22.2 since the system is employed in numerous different studies due its stability. The effect of mixture composition has also been studied on the basis of the AOT concentration that was varied from (0.1 to 0.7) mol center dot dm(-3).