Perfume containing surfactant compositions having perfume burst when diluted

Compositions yielding a maximum fragrance burst of one or more of the fragrance components of at least 20%, relative to an undiluted product, wherein said composition is defined by perfume burst index PBI:

• PBI = φ - 1.4 / CMC K
• wherein φ=oil/water partition coefficient of a selected perfume or perfume components in a mixture;
• CMC=critical micellization concentration (wt./wt.) of selected surfactant system or mixture of surfactant system in diluent or continuous phase;
• K=volatility constant of selected perfume from said continuous phase or diluent (atmospheres);
• wherein said perfume or at least one component of said perfume mixture and wherein said surfactant system or said mixture of surfactant systems are selected such that variables are calculated to provide a PBI that is greater than about 3;
• wherein by maximum fragrance burst of at least 20% is meant that the perfume concentration in the headspace above said fragrance or fragrance components increases at least 20% relative to the perfume concentration in the headspace of an undiluted product comprising the same fragrance or fragrance components measured as the composition comprising said fragrance or fragrance components is diluted below the critical micelle concentration (CMC) of the fragrance, surfactant and water system.